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【327801】2023年甘肃省武威平凉天水白银定西张掖陇南金昌酒泉庆阳中考数学真题

时间:2025-01-20 20:18:16 作者: 字数:21597字
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绝密·启用前

2023年甘肃省武威、平凉、天水、白银、定西、张掖、陇南、金昌、酒泉、庆阳中考数学真题

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一、选择题

1.9的算术平方根是(       
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
C
3
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

2. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>        
A
6
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
C
1
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

3.计算: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>        
A
2
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

4.若直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 是常数, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> )经过第一、第三象限,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的值可为(       
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
D
2

5.如图, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 是等边 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的边 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 上的高,以点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 为圆心, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 长为半径作弧交 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的延长线于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>        
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>    
A <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

6.方程 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的解为(       
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

7.如图,将矩形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 对折,使边 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 分别重合,展开后得到四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> .若 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,则四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的面积为(       
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>    
A2
B
4
C
5
D
6

8.据统计,数学家群体是一个长寿群体,某研究小组随机抽取了收录约 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 位数学家的《数学家传略辞典》中部分 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 岁及以上的长寿数学家的年龄为样本,对数据进行整理与分析,统计图表(部分数据)如下,下列结论错误的是(       

年龄范围(岁)

人数(人)

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

25

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

11

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

10

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>    
A.该小组共统计了100名数学家的年龄
B
.统计表中 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的值为5
C
.长寿数学家年龄在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 岁的人数最多
D
.《数学家传略辞典》中收录的数学家年龄在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 岁的人数估计有110

9.如图1,汉代初期的《淮南万毕术》是中国古代有关物理、化学的重要文献,书中记载了我国古代学者在科学领域做过的一些探索及成就.其中所记载的“取大镜高悬,置水盆于其下,则见四邻矣”,是古人利用光的反射定律改变光路的方法,即“反射光线与入射光线、法线在同一平面上;反射光线和入射光线位于法线的两侧;反射角等于人射角”.为了探清一口深井的底部情况,运用此原理,如图在井口放置一面平面镜可改变光路,当太阳光线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 与地面 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 所成夹角 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 时,要使太阳光线经反射后刚好垂直于地面射入深井底部,则需要调整平面镜 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 与地面的夹角 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>        
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>    
A <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

10.如图1,正方形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的边长为4 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 边的中点.动点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 从点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 出发沿 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 匀速运动,运动到点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 时停止.设点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的运动路程为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的长为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的函数图象如图2所示,则点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的坐标为(       
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>    
A <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

评卷人

得分




二、填空题

11.因式分解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ________

12.关于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的一元二次方程 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 有两个不相等的实数根,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ________(写出一个满足条件的值).

13.近年来,我国科技工作者践行“科技强国”使命,不断取得世界级的科技成果,如由我国研制的中国首台作业型全海深自主遥控潜水器“海斗一号”,最大下潜深度10907米,填补了中国水下万米作业型无人潜水器的空白;由我国自主研发的极目一号Ⅲ型浮空艇“大白鲸”,升空高度至海拔9050米,创造了浮空艇原位大气科学观测海拔最高的世界记录.如果把海平面以上9050米记作“ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 米”,那么海平面以下10907米记作“________米”.

14.如图, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 内接于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的直径,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 上一点, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ________ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>    

15.如图,菱形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,垂足分别为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,若 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ________ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>       

16.如图1,我国是世界上最早制造使用水车的国家.1556年兰州人段续的第一架水车创制成功后,黄河两岸人民纷纷仿制,车水灌田,水渠纵横,沃土繁丰.而今,兰州水车博览园是百里黄河风情线上的标志性景观,是兰州“水车之都”的象征.如图2是水车舀水灌溉示意图,水车轮的辐条(圆的半径) <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 长约为6米,辐条尽头装有刮板,刮板间安装有等距斜挂的长方体形状的水斗,当水流冲动水车轮刮板时,驱使水车徐徐转动,水斗依次舀满河水在点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 处离开水面,逆时针旋转 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 上升至轮子上方 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 处,斗口开始翻转向下,将水倾入木槽,由木槽导入水渠,进而灌溉,那么水斗从 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 处(舀水)转动到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 处(倒水)所经过的路程是________米.(结果保留 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>    

评卷人

得分




三、解答题

17.计算: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

18.解不等式组: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

19.化简: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

20.1672年,丹麦数学家莫尔在他的著作《欧几里得作图》中指出:只用圆规可以完成一切尺规作图.1797年,意大利数学家马斯凯罗尼又独立发现此结论,并写在他的著作《圆规的几何学》中.请你利用数学家们发现的结论,完成下面的作图题:
如图,已知 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 上一点,只用圆规将 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的圆周四等分.(按如下步骤完成,保留作图痕迹)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>    
以点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 为圆心, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 长为半径,自点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 起,在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 上逆时针方向顺次截取 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
分别以点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 为圆心, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 长为半径作弧,两弧交于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 上方点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
以点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 为圆心, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 长为半径作弧交 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 两点.即点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的圆周四等分.

21.为传承红色文化,激发革命精神,增强爱国主义情感,某校组织七年级学生开展“讲好红色故事,传承红色基因”为主题的研学之旅,策划了三条红色线路让学生选择:
A
.南梁精神红色记忆之旅(华池县);B.长征会师胜利之旅(会宁县);C.西路军红色征程之旅(高台县),且每人只能选择一条线路.小亮和小刚两人用抽卡片的方式确定一条自己要去的线路.他们准备了3张不透明的卡片,正面分别写上字母 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,卡片除正面字母不同外其余均相同,将3张卡片正面向下洗匀,小亮先从中随机抽取一张卡片,记下字母后正面向下放回,洗匀后小刚再从中随机抽取一张卡片.
(1)
求小亮从中随机抽到卡片 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的概率;
(2)
请用画树状图或列表的方法,求两人都抽到卡片 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的概率.

22.如图1,某人的一器官后面 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 处长了一个新生物,现需检测到皮肤的距离(图1).为避免伤害器官,可利用一种新型检测技术,检测射线可避开器官从侧面测量.某医疗小组制定方案,通过医疗仪器的测量获得相关数据,并利用数据计算出新生物到皮肤的距离.方案如下:

课题

检测新生物到皮肤的距离

工具

医疗仪器等

示意图

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

说明

如图2,新生物在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 处,先在皮肤上选择最大限度地避开器官的 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 处照射新生物,检测射线与皮肤 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的夹角为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ;再在皮肤上选择距离 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 处照射新生物,检测射线与皮肤 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的夹角为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

测量数据

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

请你根据上表中的测量数据,计算新生物 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 处到皮肤的距离.(结果精确到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> )(参考数据: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

23.某校八年级共有200名学生,为了解八年级学生地理学科的学习情况,从中随机抽取40名学生的八年级上、下两个学期期末地理成绩进行整理和分析(两次测试试卷满分均为35分,难度系数相同;成绩用 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 表示,分成6个等级: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ).下面给出了部分信息:
a
.八年级学生上、下两个学期期末地理成绩的统计图如下:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>    
b.八年级学生上学期期末地理成绩在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 这一组的成绩是:
15
151515151616161818
c
.八年级学生上、下两个学期期末地理成绩的平均数、众数、中位数如下:

学期

平均数

众数

中位数

八年级上学期

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

15

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

八年级下学期

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

19

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

根据以上信息,回答下列问题:
(1)
填空: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ________
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 为优秀,则这200名学生八年级下学期期末地理成绩达到优秀的约有________人;
(3)
你认为该校八年级学生的期末地理成绩下学期比上学期有没有提高?请说明理由.

24.如图,一次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的图象与 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 轴交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,与反比例函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的图象交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>    
(1)求点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的坐标;
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的代数式表示 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
(3)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的面积为9时,求一次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的表达式.

25.如图, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 内接于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的直径, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 上的一点, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 平分 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,垂足为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 相交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>    
(1)求证: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的切线;
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的半径为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 时,求 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的长.

26.(模型建立)
1)如图1 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 都是等边三角形,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 关于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的对称点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 边上.
求证: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
用等式写出线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的数量关系,并说明理由.
(
模型应用)
2)如图2 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 是直角三角形, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,垂足为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 关于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的对称点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 边上.用等式写出线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的数量关系,并说明理由.
(
模型迁移)
3)在(2)的条件下,若 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,求 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的值.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>    

27.如图1,抛物线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 轴交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,与直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 轴上.点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 从点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 出发,沿线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 方向匀速运动,运动到点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 时停止.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
(1)
求抛物线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的表达式;
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 时,请在图1中过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 交抛物线于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,判断四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的形状,并说明理由.
(3)
如图2,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 从点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 开始运动时,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 从点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 同时出发,以与点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 相同的速度沿 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 轴正方向匀速运动,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 停止运动时点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 也停止运动.连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,求 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的最小值.

参考答案

1.C

【解析】
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,可得9的算术平方根.
解:9的算术平方根是3
故选C

2.A

【解析】
根据等式的性质即可得出结果.
解:等式两边乘以 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
故选:A

3.B

【解析】
先计算单项式乘以多项式,再合并同类项即可.
解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
故选:B

4.D

【解析】
通过经过的象限判断比例系数k的取值范围,进而得出答案.
直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 是常数, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> )经过第一、第三象限,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的值可为2
故选:D

5.C

【解析】
由等边三角形的性质求解 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,再利用等腰三角形的性质可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,从而可得答案.
解:∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 是等边 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的边 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 上的高,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
故选C

6.A

【解析】
把分式方程转化为整式方程求解,然后解出的解要进行检验,看是否为增根.
去分母得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
解方程得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
检验: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 是原方程的解,
故选A

7.B

【解析】
由题意可得四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 是菱形, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,由菱形的面积等于对角线乘积的一半即可得到答案.
解:∵将矩形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 对折,使边 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 分别重合,展开后得到四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 互相平分,
四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 是菱形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
菱形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的面积为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
故选:B

8.D

【解析】
利用年龄范围为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的人数为10人,对应的百分比为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,即可判断A选项;由A选项可知该小组共统计了100名数学家的年龄,根据 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 即可判断B选项;由扇形统计图可知,长寿数学家年龄在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 岁的占的百分比最大,即可判断C选项;用 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 乘以小组共统计了100名数学家的年龄中在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 岁的百分比,即可判断D选项.
解:A.年龄范围为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的人数为10人,对应的百分比为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,则可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> (人),即该小组共统计了100名数学家的年龄,故选项正确,不符合题意;
B
.由A选项可知该小组共统计了100名数学家的年龄,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,故选项正确,不符合题意;
C
.由扇形统计图可知,长寿数学家年龄在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 岁的占的百分比最大,即长寿数学家年龄在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 岁的人数最多,故选项正确,不符合题意;
D
.《数学家传略辞典》中收录的数学家年龄在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 岁的人数估计有 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 人,故选项错误,符合题意.
故选:D

9.B

【解析】
如图,过 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 平面镜 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,而 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,再建立方程 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,从而可得答案.
解:如图,过 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 平面镜 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>    
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
故选B

10.C

【解析】
证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,则当PAB重合时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 最长,此时 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,而运动路程为04,从而可得答案.
解:∵正方形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的边长为4 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 边的中点,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
PAB重合时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 最长,
此时 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
运动路程为04
结合函数图象可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
故选C

11. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

【解析】
先提取公因式,再利用平方差公式分解因式即可.
解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

12. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> (答案不唯一,合理即可)

【解析】
先根据关于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的一元二次方程 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 有两个不相等的实数根得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,根据 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的取值范围,选取合适的值即可.
解:∵关于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的一元二次方程 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 有两个不相等的实数根,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 时,满足题意,
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> (答案不唯一,合理即可)

13. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

【解析】
根据正负数表示相反的意义解答即可.
解:把海平面以上9050米记作“ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 米”,则海平面以下10907米记作 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 米,
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

14.35

【解析】
由同弧所对的圆周角相等,得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 再根据直径所对的圆周角为直角,得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,然后由直角三角形的性质即可得出结果.
解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 所对的圆周角,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的直径,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
故答案为:  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

15. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

【解析】
根据菱形的性质,含 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 直角三角形的性质,及三角函数即可得出结果.
解:在菱形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
同理, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

16. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

【解析】
把半径和圆心角代入弧长公式即可;
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
故填: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

17. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

【解析】
利用二次根式的混合运算法则计算即可.
解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

18. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

【解析】
先分别解两个不等式,求出它们的解集,再求两个不等式解集的公共部分即可得到不等式组的解集.
解:解不等式组: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
解不等式①,得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
解不等式②,得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
因此,原不等式组的解集为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

19. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

【解析】
先将除法转化为乘法进行计算,再根据分式的加减计算,即可求解.
解:原式 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

20.见解析

【解析】
根据作图提示逐步完成作图即可.再根据图形基本性质进行证明即可.
解:如图,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>    
即点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的圆周四等分.
理由如下:
如图,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>    
由作图可得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,且 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 为等边三角形, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
同理可得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
AOD三点共线, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 为直径,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,而 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
由作图可得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,而 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
由作图可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
同理 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的圆周四等分.

21.(1) <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

【解析】
1)本题考查了等可能时间的概率,带入公式即可求解;
2)先用列表法或树状图法列举出所有可能的情况,再带入公式计算即可.
1 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> (小亮抽到卡片 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
2)列表如下:

小刚


小亮

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

或画树状图如下:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
共有9种等可能的结果,两人都抽到卡片 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的结果有1种,
所以, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> (两人都抽到卡片 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

22.新生物 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 处到皮肤的距离约为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

【解析】
过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,垂足为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,用  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的正切值表示出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 中,用 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的正切值表示出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,由 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,联立求解 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 即可.
解:过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,垂足为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
由题意得, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>        
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
答:新生物 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 处到皮肤的距离约为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

23.(1)16
(2)35
(3)
八年级,理由见解析

【解析】
1)由中位数的概念,可知40人成绩的中位数是第2021位的成绩;
2)根据样本估计总体即可求解;
3)根据平均成绩或中位数即可判断.
1)解:由中位数的概念,可知40人成绩的中位数是第2021位的成绩,
由统计图知A4人,B10人,C10人,则中位数在C组,第2021位的成绩分别是1616
则中位数是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
故答案为:16
2)解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ()
200名学生八年级下学期期末地理成绩达到优秀的约有35人,
故答案为:35
3)解:因为抽取的八年级学生的期末地理成绩的平均分(或中位数)下学期的比上学期的高,所以八年级学生下学期期末地理成绩更好.

24.(1) <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
(3)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

【解析】
1)把点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 代入 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,从而可得答案;
2)把点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 代入 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,从而可得答案;
3)利用三角形的面积先求解 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的坐标,可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,代入再解决 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的值即可.
1)解:∵点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 在反比例函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的图象上,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
2)∵点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 在一次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的图象上,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
3)如图,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>    
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
一次函数的表达式为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

25.(1)见解析
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

【解析】
1)根据同弧所对的圆周角相等,得出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,根据 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 得出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,角平分线的定义得出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,等量代换得出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,进而得出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,即 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,即可得证;
2)连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,进而证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,得出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,解 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,得出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,进而根据 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 即可求解.
1)证明:∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 平分 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,即 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的半径,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的切线.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>    
2)连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的直径,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

26.1)①见解析;② <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,理由见解析;(2 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,理由见解析;(3 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

【解析】
1)①证明: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,再证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 即可;②由 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 关于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 对称,可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> .证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,从而可得结论;
2)如图,过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> .可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,从而可得结论;
3)由 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,结合 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,求解 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,如图,过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> .可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,再利用余弦的定义可得答案.
1)①证明:∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 都是等边三角形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>    
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> .理由如下:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 关于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 对称,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
2 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> .理由如下:
如图,过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>        
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 关于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 对称,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 是直角三角形, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,即 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
3)∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
如图,过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>    
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

27.(1) <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
(2)
四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 是平行四边形,理由见解析
(3)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>

【解析】
1)用待定系数法求二次函数解析式即可;
2)作 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 交抛物线于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,垂足为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,由点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 上,可知 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,得出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,进而得出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,然后证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,即可得出结论;
3)由题意得, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> .在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 上方作 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,使得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,根据 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 得出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的最小值为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,利用勾股定理求得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,即可得解.
1)解:∵抛物线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
2)四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 是平行四边形.
理由:如图1,作 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 交抛物线于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,垂足为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 上,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 轴, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 轴,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 是平行四边形;
3)如图2,由题意得, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 上方作 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> ,使得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> (当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 三点共线时最短),
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的最小值为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a> 的最小值为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1010/" title="甘肃省" class="c1" target="_blank">甘肃省</a> <a href="/tags/1011/" title="金昌" class="c1" target="_blank">金昌</a> <a href="/tags/1013/" title="天水" class="c1" target="_blank">天水</a> <a href="/tags/1095/" title="白银" class="c1" target="_blank">白银</a> <a href="/tags/1096/" title="平凉" class="c1" target="_blank">平凉</a>