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【327954】2024年陕西省中考数学试题

时间:2025-01-20 20:49:26 作者: 字数:15292字
简介:

绝密★启用前

200738-2024年陕西省中考数学试题


学校:___________姓名:___________班级:___________考号:___________


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


一、单选题

1  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的倒数是(      )

A  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> B  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> C  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> D  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

2.如图,将半圆绕直径所在的虚线旋转一周,得到的立体图形是(      )

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

A.  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> B.  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> C.  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> D.  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

3.如图,  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,则  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的度数为(      )

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

A  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>     B  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>     C  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>     D  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

4.不等式  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的解集是(      )

A  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>     B  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>     C  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>     D  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

5.如图,在  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 中,  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 边上的高,  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的中点,连接  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,则图中的直角三角形有(      )

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>   

A2个    B3个    C4个    D5

6.一个正比例函数的图象经过点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 和点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,若点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 与点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 关于原点对称,则这个正比例函数的表达式为 (      )

A  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>     B  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>     C  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>     D  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

7.如图,正方形  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的顶点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 在正方形  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的边  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 上,  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 交于点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,若  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,则  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的长为(      )

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

A2    B3    C  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>     D  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

8.已知一个二次函数  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的自变量  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 与函数  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的几组对应值如下表:

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

0

3

5

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

0

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

则下列关于这个二次函数的结论正确的是(      )

A. 图象的开口向上

B.  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 时,  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的值随  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 值的增大而减小

C. 图象经过第二、三、四象限

D. 图象的对称轴是直线  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

二、填空题

9.分解因式:  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>                

10.小华探究“幻方”时,提出了一个问题:如图,将  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,, <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 这五个数分别填在五个小正方形内,使横向三个数之和与纵向三个数之和相等,则填入中间位置的小正方形内的数可以是        .(写出一个符合题意的数即可)

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

11.如图,  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的弦,连接  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 所对的圆周角,则  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的和的度数是        .

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

(第3题图)

12.已知点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 和点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 均在反比例函数  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的图象上,若  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,则  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>         0

13.如图,在  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 中,  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 是边  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 上一点,连接  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,在  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 右侧作  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,且  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,连接  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> .若  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,则四边形  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的面积为        

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

三、解答题

14.计算:  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

15.先化简,再求值:  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,其中  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

16.解方程:  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> .

17.如图,已知直线ll外一点A,请用尺规作图法,求作一个等腰直角  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,使得顶点B和顶点C都在直线l上.(作出符合题意的一个等腰直角三角形即可,保留作图痕迹,不写作法)

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

18.如图,四边形  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 是矩形,点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 和点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 在边  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 上,且  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> .求证:  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

19.一个不透明的袋子中共装有五个小球,其中3个红球,1个白球,1个黄球,这些小球除颜色外都相同.将袋中小球摇匀,从中随机摸出一个小球记下颜色后放回,记作随机摸球一次.

(1)随机摸球10次,其中摸出黄球3次,则这10次摸球中,摸出黄球的频率是        

(2)随机摸球2次,用画树状图或列表的方法,求这两次摸出的小球都是红球的概率.

20.星期天,妈妈做饭,小峰和爸爸进行一次家庭卫生大扫除,根据这次大扫除的任务量,若小峰单独完成,需  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ;若爸爸单独完成,需  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,当天,小峰先单独打扫了一段时间后,去参加篮球训练,接着由爸爸单独完成剩余的打扫任务,小峰和爸爸这次一共打扫了  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,求这次小峰打扫了多长时间.

21.如图所示,一座小山顶的水平观景台的海拔高度为  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,小明想利用这个观景台测量对面山顶  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 点处的海拔高度,他在该观景台上选定了一点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,在点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 处测得  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 点的仰角  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,再在  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 上选一点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,在点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 处测得  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 点的仰角  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> .求山顶  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 点处的海拔高度.(小明身高忽略不计,参考数据:  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>   

22.我国新能源汽车快速健康发展,续航里程不断提升,王师傅驾驶一辆纯电动汽车从  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 市前往  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 市,他驾车从  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 市一高速公路入口驶入时,该车的剩余电量是  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,行驶了  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 后,从  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 市一高速公路出口驶出,已知该车在高速公路上行驶的过程中,剩余电量  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 与行驶路程  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 之间的关系如图所示.

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

(1)  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 之间的关系式;

(2)已知这辆车的“满电量”为  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,求王师傅驾车从  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 市这一高速公路出口驶出时,该车的剩余电量占“满电量”的百分之多少?

23.水资源问题是全球关注的热点,节约用水已成为全民共识.某校课外兴趣小组想了解居民家庭用水情况,他们从一小区随机抽取了30户家庭,收集了这30户家庭去年7月份的用水量,并对这30个数据进行整理,绘制了如下统计图表,

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

组别

用水量  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

组内平均数  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

A

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

B

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

C

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

D

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

根据以上信息,解答下列问题.

(1)30个数据的中位数落在        组(填组别);

(2)求这30户家庭去年7月份的总用水量;

(3)该小区有1000户家庭,若每户家庭今年7月份的用水量都比去年7月份各自家庭的用水量节约  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,请估计这1000户家庭今年7月份的总用水量比去年7月份的总用水量节约多少  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ?

24.如图,直线  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 相切于点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的直径,点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 上,且位于点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 两侧,连接  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,分别与  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 交于点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,连接  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

(1)求证:  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

(2)  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的半径  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,求  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的长.

25.一条河上横跨着一座宏伟壮观的悬索桥.桥梁的缆索  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 与缆索  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 均呈抛物线型,桥塔  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 与桥塔  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 均垂直于桥面,如图所示,以  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 为原点,以直线  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 轴,以桥塔  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 所在直线为  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 轴,建立平面直角坐标系.

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>     

已知:缆索  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 所在抛物线与缆索  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 所在抛物线关于  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 轴对称,桥塔  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 与桥塔  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 之间的距离  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,缆索  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的最低点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的距离  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> (桥塔的粗细忽略不计)

(1)求缆索  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 所在抛物线的函数表达式;

(2)  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 在缆索  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 上,  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,且  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,求  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的长.

26问题提出

1)如图1,在  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 中,  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,作  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的外接圆  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> .则  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的长为        ;(结果保留π

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>   

问题解决

2)如图2所示,道路  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的一侧是湿地.某生态研究所在湿地上建有观测点 ,, <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,线段  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 为观测步道,其中点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 和点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 为观测步道出入口,已知点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 上,且  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,现要在湿地上修建一个新观测点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,使  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> .再在线段  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 上选一个新的步道出入口点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,并修通三条新步道 ,, <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,使新步道  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 经过观测点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,并将五边形  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的面积平分.

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>   

请问:是否存在满足要求的点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 和点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ?若存在,求此时  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的长;若不存在,请说明理由.(点 ,,,, <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 在同一平面内,道路  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 与观测步道的宽、观测点及出入口的大小均忽略不计,结果保留根号)

参考答案

一、单选题

1. C

解:  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的倒数是  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> .

故此答案C


2. C

将一个半圆绕它的直径所在的直线一周得到的立体形是球,故C.


3. B

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

故此答案B


4. D

解:  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,去括号得  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,移合并得  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,解得  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

故此答案D


5. C

解:由  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 直角三角形,共有4个直角三角形.故此答案C


6. A

解:  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 与点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 关于原点称,

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

正比例函数的解析式  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,把  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 代入,得  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> .

故此答案A


7. B

解:正方形  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

正方形  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

意得  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,即  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

解得  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,故此答案B


8. D

意得  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 解得  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 二次函数的表达式  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 象的开口向下,故选项A不符合意;象的是直线  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,故选项D符合意;当  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的增大而增大,当  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的增大而减小,故选项B不符合意;  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 点坐标为  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,且经过原点,象的开口向下,  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 经过第一、三、四象限,故选项C不符合.D.


二、填空题

9. aab).

解:  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> =aa﹣b).


10. 0

解:由意,填写如下:

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> .


11.  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 周角,  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 心角,  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,即  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> .故答案  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> .


12.  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

解:  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 和点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 均在反比例函数  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 象上,  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>


13. 60

解:  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 平分  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> .

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,且  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的面  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

由勾股定理得  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

解得  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的面积为60


三、解答题

14.  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

解:  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>


15.  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

解:  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,原式  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>


16. 【解】去分母得  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,去括号得  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,移项、合并同类项得  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> .检验:把  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 代入  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 得,  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 是原方程的解.

17. 见解析

解:等腰直角  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 所示:

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>


18. 见解析

明:  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 是矩形,  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,即  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>


19. (1)0.3(2)  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

1)解:由意得摸出黄球的率是  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

2)解:画得,

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

共有25种等可能的果,其中两次摸出的小球都是球有9果,

两次摸出的小球都是球的概率  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>


20. 小峰打扫了  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

解:设总工作量1,小峰打  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,爸爸打  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 小峰打的工作效率  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,爸爸打的工作效率  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

意得,  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,解得  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

答:小峰打  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>


21. 山顶  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 点处的海拔高度为  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

解:  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的延长线于点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>   

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 中,  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 中,  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,解得  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的海拔高度  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>


22. (1)  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 之间的关系式为  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> (2)该车的剩余电量占“满电量”的  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

1)解:  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的关系式  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 代入得  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

解得  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的关系式  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

2)解:当  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

答:该车的剩余量占满电  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>


23. (1)B(2)  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> (3)  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

1)解:根据条形统计图可知,  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 10B12C6D2

30个数据从小到大行排序,排在第1516的两个数据一定落在B

30个数据的中位数落在B

2)解:30家庭去年7月份的用水量  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

3)解:去年每家庭7月份的用水量约为  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

家庭今年7月份的用水量都比去年7月份各自家庭的用水量节约  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

今年每家庭7月份的节约用水量约为  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

计这1000家庭今年7月份的用水量比去年7月份的用水量节约  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>


24. (1)见解析;(2)  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

1明:线  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 相切于点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的直径,  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

2)解:  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

线  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 相切于点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 是等腰直角三角形,  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的直径,  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 也是等腰直角三角形,  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,即  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>


25. (1)  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> (2)  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的长为  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

1)解:由意得  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的坐标为  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的坐标为  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

设缆  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 所在抛物线的函数表达式  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 代入得  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,解得  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 所在抛物线的函数表达式  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

2)解:  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 所在抛物线  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 所在抛物线关于  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 轴对称,

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 所在抛物线的函数表达式  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 代入得  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,解得  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 长为  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>


26. ()π <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ;(2)存在满足要求的点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 和点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,此时  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的长为  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

解:(1  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>   

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 三角形,

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

ππ <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

2)存在足要求的点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 和点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,此  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 长为  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> .理由如下,

解:  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 是平行四形,

要在湿地上修建一个新观测  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,使  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 在以  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 为圆心,  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 弦,心角  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 上,如

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>   

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

经过  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的直线都平分四  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的面

新步道  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 经过观测  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,并将五  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的面平分,

线  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 经过  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的中点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 的中位线

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 是平行四形,

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 于点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>   

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 是平行四形,  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,即  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 中,  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

 <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>

答:存在足要求的点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 和点  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> ,此  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a> 长为  <a href="/tags/51/" title="试题" class="c1" target="_blank">试题</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/895/" title="陕西省" class="c1" target="_blank">陕西省</a> <a href="/tags/1105/" title="陕西" class="c1" target="_blank">陕西</a>