当前位置:首页 > 中考 > 数学试卷

【327869】2023年山东省泰安市中考数学真题

时间:2025-01-20 20:31:40 作者: 字数:22228字

绝密·启用前

2023年山东省泰安市中考数学真题

题号

总分

得分





注意事项:

1.答题前填写好自己的姓名、班级、考号等信息

2.请将答案正确填写在答题卡上



评卷人

得分




一、选择题

1. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的倒数是(     
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>

2.下列运算正确的是(       
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>

3.2023117日,国家航天局公布了我国嫦娥五号月球样品的科研成果.科学家们通过对月球样品的研究,精确测定了月球的年龄是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 亿年,数据 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 亿年用科学记数法表示为(       
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>       
A <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>

4.小亮以四种不同的方式连接正六边形的两条对角线,得到如下四种图形,则既是轴对称图形又是中心对称图形的是(       
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>    
B <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>    
C <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>    
D <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>    

5.把一块直角三角板和一把直尺如图放置,若 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的度数等于(       
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>    
A <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>

6.为了解学生的身体素质状况,国家每年都会进行中小学生身体素质抽测.在今年的抽测中,某校九年级二班随机抽取了 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 名男生进行引体向上测试,他们的成绩(单位:个)如下: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> .根据这组数据判断下列结论中错误的是(       
A
.这组数据的众数是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
B
.这组数据的中位数是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
C
.这组数据的平均数是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
D
.这组数据的方差是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>

7.如图, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的直径,DC <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 上的点, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的度数是(       
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>    
A <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>

8.一次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 与反比例函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ab为常数且均不等于0)在同一坐标系内的图象可能是(       
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>    
B <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>    
C <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>    
D <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>    

9.如图, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的外接圆,半径为4,连接OBOCOA,若 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,则阴影部分的面积是(       
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>    
A <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>

10.《九章算术》是我国古代数学的经典著作,书中有一个问题:“今有黄金九枚,白银一十一枚,称之重适等,交易其一,金轻十三两,问金、银各重几何?”意思是:甲袋中装有黄金9枚(每枚黄金重量相同),乙袋中装有白银11枚(每枚白银重量相同),称重两袋相等,两袋互相交换1枚后,甲袋比乙袋轻了13两(袋子重量忽略不计),问黄金、白银每枚各重多少两?设每枚黄金重x两,每枚白银重y两.根据题意得(       
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>

11.如图, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 是等腰三角形, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> .以点B为圆心,任意长为半径作弧,交AB于点F,交BC于点G,分别以点F和点G为圆心,大于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的长为半径作弧,两弧相交于点H,作射线BHAC于点D;分别以点B和点D为圆心,大于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的长为半径作弧,两孤相交于MN两点,作直线MNAB于点E,连接DE.下列四个结论:① <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ;② <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ;③ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ;④当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> .其中正确结论的个数是(       
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>    
A1
B
2
C
3
D
4

12.如图,在平面直角坐标系中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的一条直角边 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> x轴上,点A的坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,点M <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 中点,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> .将 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 以点O为旋转中心按顺时针方向旋转,在旋转过程中,线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的最小值是(       
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>    
A3
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
D
2

评卷人

得分




二、填空题

13.已知关于x的一元二次方程 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 有两个不相等的实数根,则a的取值范围是_______

14.为了测量一个圆形光盘的半径,小明把直尺、光盘和三角尺按图所示放置于桌面上,并量出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,则这张光盘的半径是_______ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> .(精确到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> .参考数据: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>    

15.二次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的最大值是__________

16.在一次综合实践活动中,某学校数学兴趣小组对一电视发射塔的高度进行了测量.如图,在塔前C处,测得该塔顶端B的仰角为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,后退 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> )到D处有一平台,在高 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> )的平台上的E处,测得B的仰角为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> .则该电视发射塔的高度 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> _______ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> .(精确到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> .参考数据: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>    

17.如图,在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,点D <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 上,点E <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 上,点B关于直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的轴对称点为点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,分别与 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 相交于F点,G点,若 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的长度为__________
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>    

18.已知, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 都是边长为2的等边三角形,按下图所示摆放.点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 都在x轴正半轴上,且 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,则点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的坐标是______
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>       

评卷人

得分




三、解答题

19.1)化简: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
2)解不等式组: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>

20.20221016日至1022日,中国共产党第二十次全国代表大会在北京召开.为激励青少年争做党的事业接班人,某市团市委在党史馆组织了“红心永向党”为主题的知识竞赛,依据得分情况将获奖结果分为四个等级:A级为特等奖,B级为一等奖,C级为二等奖,D级为优秀奖.并将统计结果绘制成了如图所示的两幅不完整的统计图.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>    
请根据相关信息解答下列问题:
(1)
本次竞赛共有______名选手获奖,扇形统计图中扇形C的圆心角度数是______度;
(2)
补全条形统计图;
(3)
若该党史馆有一个入口,三个出口.请用树状图或列表法,求参赛选手小丽和小颖由馆内恰好从同一出口走出的概率.

21.如图,一次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的图象与反比例函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的图象分别交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,与 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 轴, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 轴分别交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,作 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 轴,垂足为点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>    
(1)求反比例函数的表达式;
(2)
在第二象限内,当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 时,直接写出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的取值范围;
(3)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 轴负半轴上,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,且 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,求点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 坐标.

22.为进行某项数学综合与实践活动,小明到一个批发兼零售的商店购买所需工具.该商店规定一次性购买该工具达到一定数量后可以按批发价付款,否则按零售价付款.小明如果给学校九年级学生每人购买一个,只能按零售价付款,需用3600元;如果多购买60个,则可以按批发价付款,同样需用3600元,若按批发价购买60个与按零售价购买50个所付款相同,求这个学校九年级学生有多少人?

23.如图,矩形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 中,对角线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 相交于点O,点F <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 边上的一点,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,将 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 沿直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 折叠,点D落在点G处,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 并延长交 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 于点H,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 并延长交 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 于点M,交 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的延长线于点E,且 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>    
(1)求证:四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 是平行四边形;
(2)
求证: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>

24.如图, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 是两个等腰直角三角形, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>    
(1) <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 时,求 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
(2)
求证: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
(3)
求证: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>

25.如图1,二次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的图象经过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>    
(1)求二次函数的表达式;
(2)
若点P在二次函数对称轴上,当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 面积为5时,求P坐标;
(3)
小明认为,在第三象限抛物线上有一点D,使 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ;请判断小明的说法是否正确,如果正确,请求出D的坐标;如果不正确,请说明理由.

参考答案

1.D

【解析】
根据乘积是1的两个数叫做互为倒数解答.
解:∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的倒数是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
故选:D

2.D

【解析】
A
、不能合并,本选项错误;B、利用完全平方公式展开得到结果,即可作出判断;CD、利用积的乘方及幂的乘方运算法则计算得到结果,即可作出判断.
解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 不是同类项,不能合并,故A选项错误,不符合题意;
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,故B选项错误,不符合题意;
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,故C选项错误,不符合题意;
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,故D选项正确,符合题意;
故选:D

3.B

【解析】
科学记数法的表现形式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的形式,其中 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> n为整数,确定n的值时,要看把原数变成a时,小数点移动了多少位,n的绝对值与小数点移动的位数相同,当原数绝对值大于等于10时,n是正数,当原数绝对值小于1n是负数;由此进行求解即可得到答案.
解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 亿年 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 年,
故选B

4.D

【解析】
根据轴对称图形的概念:如果一个图形沿一条直线折叠,直线两旁的部分能够互相重合,这个图形叫做轴对称图形;根据中心对称图形的概念:在平面内,把一个图形绕着某个点旋转180度后与原图重合,即可得到答案.
解:A、既不是轴对称图形也不是中心对称图形,故该选项不符合题意;
B
、既不是轴对称图形也不是中心对称图形,故该选项不符合题意;
C
、既不是轴对称图形也不是中心对称图形,故该选项不符合题意;
D
、是轴对称图形也是中心对称图形,故该选项符合题意;
故选:D

5.B

【解析】
如图所示,过点O <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,由平行线的性质得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,进而推出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,由此即可得到答案.
解:如图所示,过点O <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
故选B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>    

6.B

【解析】
根据众数的定义,中位数,平均数,方差的计算方法即可求解.
解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 、这组数据中出现次数最多的是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,故众数是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,正确,不符合题意;
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 、这组数据重新排序为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,故中位数是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,错误,符合题意;
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 、这组数据的平均数是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,故平均数是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,正确,不符合题意;
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 、这组数据的平均数是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,方差是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,故方差是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,正确,不符合题意;
故选: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>

7.A

【解析】
根据圆内接四边形对角互补和直径所对圆周角等于90度求解即可.
解:∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的直径,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
故选:A

8.D

【解析】
先根据一次函数图象确定ab的符号,进而求出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的符号,由此可以确定反比例函数图象所在的象限,看是否一致即可.
解:A、∵一次函数图象经过第一、二、三象限,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
反比例函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的图象见过第一、三象限,这与图形不符合,故A不符合题意;
B
、∵一次函数图象经过第一、二、四象限,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
反比例函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的图象见过第二、四象限,这与图形不符合,故B不符合题意;
C
、∵一次函数图象经过第一、三、四象限,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
反比例函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的图象见过第二、四象限,这与图形不符合,故C不符合题意;
D
、∵一次函数图象经过第一、二、四象限,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
反比例函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的图象见过第二、四象限,这与图形符合,故D符合题意;
故选D

9.C

【解析】
先根据等腰三角形的性质以及三角形内角和定理求得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,再根据扇形的面积公式即可求解.
解:∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
故选:C

10.C

【解析】
根据题意可得等量关系:①9枚黄金的重量 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 11枚白银的重量;②(10枚白银的重量 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 枚黄金的重量) <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 1枚白银的重量 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 枚黄金的重量) <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 两,根据等量关系列出方程组即可.
解:设每枚黄金重x两,每枚白银重y两,
由题意得, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
故选C

11.C

【解析】
根据等腰三角形两底角相等与 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,根据角平分线定义得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,根据线段垂直平分线性质得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,推出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,推出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,①正确;根据等角对等边得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,根据三角形外角性质得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,推出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,②正确;根据 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,推出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,③错误;根据 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 时,  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,推出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,④正确.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
由作图知, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 平分 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 垂直平分 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,①正确;
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,②正确;
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,③错误;
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,④正确
正确的有①②④,共3个.
故选:C

12.A

【解析】
如图所示,延长 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> E,使得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,根据点A的坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,再证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的中位线,得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ;解 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,进一步求出点C在以O为圆心,半径为4的圆上运动,则当点M在线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 上时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 有最小值,即此时 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 有最小值,据此求出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的最小值,即可得到答案.
解:如图所示,延长 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> E,使得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的一条直角边 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> x轴上,点A的坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
M <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 中点,点A <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 中点,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的中位线,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 以点O为旋转中心按顺时针方向旋转,
C在以O为圆心,半径为4的圆上运动,
当点M在线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 上时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 有最小值,即此时 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 有最小值,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的最小值为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的最小值为3
故选A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>    

13. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ## <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>

【解析】
利用一元二次方程根的判别式求解即可.
解:∵关于x的一元二次方程 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</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/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>

14. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>

【解析】
设光盘的圆心为O,三角尺和光盘的切点为C,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,经过圆外一点A的两条直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 都与圆O相切,所以 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的角平分线, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,同时由切线的性质得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,求出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,即为圆的半径,进而确定出圆的直径.
解:设光盘的圆心为O,三角尺和光盘的切点为C,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,如下图所示:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>    
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 分别为圆O的切线,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的角平分线,即 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
又∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
则这张光盘的半径为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>

15. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>

【解析】
利用配方法把二次函数一般式化为顶点式,即可求解.
解:利用配方法,将一般式化成顶点式:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 二次函数开口向下,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 顶点处取最大值,
即当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 时,最大值为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>

16.55

【解析】
如图所示,过点E <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> F,则四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 是矩形,可得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ;设 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,解 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,解 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,进而建立方程 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
,解方程即可得到答案.
解:如图所示,过点E <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> F
由题意得, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 是矩形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
故答案为:55
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>    

17. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>

【解析】
根据等边对等角和折叠的性质证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,进而证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,然后代值计算求出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
解:∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
由折叠的性质可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
又∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,即 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>

18. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>

【解析】
先确定前几个点的坐标,然后归纳规律,按规律解答即可.
解:由图形可得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
如图:过 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 轴,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>    
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,
同理: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 为偶数, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 为奇数;
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 2023为奇数
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
故答案为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>

19.1 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ;(2 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>

【解析】
1)根据分式的混合计算法则求解即可;
2)先求出每个不等式的解集,再根据 “同大取大,同小取小,大小小大中间找,大大小小找不到(无解)”求出不等式组的解集即可.
解:(1 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
2 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
解不等式①得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
解不等式②得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
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/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>

20.(1)200108
(2)
见解析
(3)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>

【解析】
1)用A级的人数除以其人数占比即可求出获奖选手的总数,进而求出B级的人数,由此即可求出C级的人数,再用360度乘以C级的人数占比即可得到答案;
2)求出B级的人数,然后补全统计图即可;
3)先列出表格得到所有等可能性的结果数,再找到符合题意得结果数,最后依据概率计算公式求解即可.
1)解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 名,
本次竞赛共有200名选手获奖,
C级的人数为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 名,
扇形统计图中扇形C的圆心角度数是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 度,
故答案为:200108
2)解:B级的人数为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 名,
补全统计图如下:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>    
3)解:设这三个出口分别用EFG表示,列表如下:


E

F

G

E

EE

FE

GE

F

EF

FF

GF

G

EG

FG

GG

由表格可知一共有9种等可能性的结果数,其中参赛选手小丽和小颖由馆内恰好从同一出口走出的结果数有3种,
参赛选手小丽和小颖由馆内恰好从同一出口走出的概率 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>

21.(1) <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
(3)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>

【解析】
1)求出点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 坐标,即可求出反比例函数解析式;
2)观察图象特点,即可得出取值范围;
3)先证明三角形相似,再根据相似三角形的性质求出线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 长,最后由线段和差即可求出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的长.
1)∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 轴,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的纵坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 图象上,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
反比例函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的图象过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
反比例函数的表达式为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
2)如图,在第二象限内,当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>    
3)如图,过 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 轴于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>    
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 轴,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 是矩形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,即: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>

22.这个学校九年级学生有300人.

【解析】
设零售价为x元,批发价为y,然后根据题意列二元一次方程组求得零售价为12元,然后用3600除以零售价即可解答.
解:设零售价为x元,批发价为y
根据题意可得:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
则学校九年级学生 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 人.
答:这个学校九年级学生有300人.

23.(1)证明见解析
(2)
证明见解析

【解析】
1)根据矩形的性质和折叠的性质证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,由此即可证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,进而推出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,再由 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,即可证明四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 是平行四边形;
2)由(1)的结论可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,进一步证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,再证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,即可证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
1)证明:∵四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 是矩形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
由折叠的性质可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
又∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 是平行四边形;
2)证明:∵四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 是平行四边形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
由折叠的性质可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
又∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>

24.(1) <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
(2)
见详解
(3)
见详解

【解析】
1)先证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,再证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 是线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的垂直平分线,即有 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,即 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 是等边三角形,问题得解;
2)根据垂直可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,又根据 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,即可证明;
3)过H点作 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 于点K,先表示出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,根据 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 是线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的垂直平分线,可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,即可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,进而可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,则有 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,结合 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,再证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,即可证明.
1)∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 是两个等腰直角三角形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
等腰直角 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 是线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的垂直平分线,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,即 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 是等边三角形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
2)在(1)中有 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
又∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
3)过H点作 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 于点K,如图,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>    
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,即是等腰 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 是线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的垂直平分线,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
在(1)中已证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>

25.(1) <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
(3)
正确, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>

【解析】
1)直接运用待定系数法求解即可;
2)首先求出直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 解析式,然后通过设 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 点坐标,并表示对应 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 点坐标,从而利用“割补法”计算 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的面积表达式并建立方程求解即可;
3)首先连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,设 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 与对称轴交点为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,对称轴与 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 轴交点为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,延长 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 与对称轴交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,根据已知信息求出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,然后推出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,从而在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 中求出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,确定出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 点坐标,再求出直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 解析式,通过与抛物线解析式联立,求出交点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的坐标即可.
1)解:将 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 代入 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 得:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
抛物线解析式为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
2)解:由抛物线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 可知,其对称轴为直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
设直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 解析式为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 代入解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 解析式为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
此时,如图所示,作 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 轴,交 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>    
P在二次函数对称轴上,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
要使得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 面积为5
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 的坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
3)解:正确, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,理由如下:
如图所示,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,设 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 与对称轴交点为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,对称轴与 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 轴交点为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,延长 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 与对称轴交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>    
由(1)、(2)可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
根据抛物线的对称性, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
即:在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
设直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 解析式为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 代入解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> 解析式为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>
联立 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> ,解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a> (不合题,舍去)
小明说法正确,D的坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/561/" title="山东" class="c1" target="_blank">山东</a> <a href="/tags/995/" title="山东省" class="c1" target="_blank">山东省</a> <a href="/tags/1000/" title="泰安" class="c1" target="_blank">泰安</a>