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【327740】2022年内蒙古呼和浩特市中考数学真题

时间:2025-01-20 20:07:34 作者: 字数:23996字
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2022年内蒙古呼和浩特市中考数学真题

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得分





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评卷人

得分




一、选择题

1.计算 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的结果是(       
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
B
1
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
D
5

2.2022526日央视新闻报道,今年我国农发行安排夏粮收购准备金1100亿元.数据“1100亿”用科学记数法表示为(       
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

3.不透明袋中装有除颜色外完全相同的 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 个白球、 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 个红球,则任意摸出一个球是红球的概率是(       
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

4.图中几何体的三视图是(       
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

5.学校开展“书香校园,师生共读”活动,某学习小组五名同学一周的课外阅读时间(单位: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ),分别为:455610.这组数据的平均数、方差是(       
A
64.4
B
56
C
64.2
D
65

6.下列运算正确的是(       
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

7.如图, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,将 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 绕点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 顺时针旋转得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,使点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的对应点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 恰好落在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 边上, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> .若 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的度数是(用含 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的代数式表示)(       
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

8.已知 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 是方程 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的两个实数根,则代数式 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的值是(       
A
4045
B
4044
C
2022
D
1

9.如图,四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 是菱形, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 中点, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 是对角线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 上一点,且 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的值是(       
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
A
3
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

10.以下命题:①面包店某种面包售价 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> /个,因原材料涨价,面包价格上涨10%,会员优惠从打八五折调整为打九折,则会员购买一个面包比涨价前多花了 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 元;②等边三角形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 边上一点, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 边上一点,若 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ;③两边及第三边上的中线对应相等的两个三角形全等;④一列自然数012355,依次将该列数中的每一个数平方后除以100,得到一列新数,则原数与对应新数的差,随着原数的增大而增大.其中真命题的个数有(       
A
1
B
2
C
3
D
4

评卷人

得分




二、填空题

11.因式分解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ______

12. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 在反比例函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的图象上,若 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的取值范围是______

13.如图,从一个边长是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的正五边形纸片上剪出一个扇形,这个扇形的面积为_______(用含 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的代数式表示);如果将剪下来的扇形围成一个圆锥,圆锥的底面圆直径为_______
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

14.某超市糯米的价格为5/千克,端午节推出促销活动:一次购买的数量不超过2千克时,按原价售出,超过2千克时,超过的部分打8折.若某人付款14元,则他购买了_______千克糯米;设某人的付款金额为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 元,购买量为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 千克,则购买量 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 关于付款金额 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的函数解析式为______

15.已知 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 为⊙ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的直径且 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 是⊙ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 上一点(不与 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 重合),点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 在半径 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 上,且 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 与过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的⊙ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的切线垂直,垂足为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> .若 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> _____ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> _______

16.在平面直角坐标系中,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 和点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的坐标分别为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,抛物线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 与线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 只有一个公共点,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的取值范围是______

评卷人

得分




三、解答题

17.计算求解:
(1)
计算 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
(2)
解方程组 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

18.一去紫台连朔漠,独留青冢向黄昏”,美丽的昭君博物院作为著名景区现已成为外地游客到呼和浩特市旅游的打卡地.如图,为测量景区中一座雕像 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的高度,某数学兴趣小组在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 处用测角仪测得雕像顶部 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的仰角为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,测得底部 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的俯角为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> .已知测角仪 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 与水平地面垂直且高度为1米,求雕像 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的高.(用非特殊角的三角函数及根式表示即可)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

19.某商场服装部为了调动营业员的积极性,决定实行目标管理,根据目标完成的情况对营业员进行适当的奖励.为了确定一个适当的月销售目标,商场服装部统计了每位营业员在某月的销售额(单位:万元),数据如下:17   18   16   13   24   15   27   26   18   19   22   17   16   19   32   30   16   15   16   28   15   32   23   17   14   15   27   27   16   19,对这30个数据按组距3进行分组,并整理和分析如下:
频数分布表:

组别

销售额/万元

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

频数

6

10

3

3

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

2


数据分析表:

平均数

众数

中位数

20.3

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>


请根据以上信息解答下列问题:
(1)
上表中 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
(2)
若想让一半左右的营业员都能达到销售目标,你认为月销售额定为多少合适?说明理由;
(3)
若从第六组和第七组内随机选取两名营业员在表彰会上作为代表发言,请你直接写出这两名营业员在同一组内的概率.

20.如图,在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,以 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 为直径的⊙ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,交线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的延长线于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
(1)
求证: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,求 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

21.如图,在平面直角坐标系中,一次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的图象与反比例函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的图象交于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 两点,且 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 点的横坐标为1,过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 轴, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 是直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 上一点,且 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
(1)
求一次函数与反比例函数的解析式;
(2)
根据图象,请直接写出不等式 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的解集.

22.今年我市某公司分两次采购了一批土豆,第一次花费30万元,第二次花费50万元,已知第一次采购时每吨土豆的价格比去年的平均价格上涨了200元,第二次采购时每吨土豆的价格比去年的平均价格下降了200元,第二次的采购数量是第一次采购数量的2倍.
(1)
问去年每吨土豆的平均价格是多少元?
(2)
该公司可将土豆加工成薯片或淀粉,因设备原因,两种产品不能同时加工,若单独加工成薯片,每天可加工5吨土豆,每吨土豆获利700元;若单独加工成淀粉,每天可加工8吨土豆,每吨土豆获利400元.由于出口需要,所有采购的土豆必须全部加工完且用时不超过60天,其中加工成薯片的土豆数量不少于加工成淀粉的土豆数量的 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,为获得最大利润,应将多少吨土豆加工成薯片?最大利润是多少?

23.下面图片是八年级教科书中的一道题:如图,四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 是正方形,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 是边 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的中点, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,且 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 交正方形外角的平分线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> .求证 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> .(提示:取 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的中点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> .)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
(1)
请你思考题中“提示”,这样添加辅助线的意图是得到条件:
(2)
如图1,若点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 边上任意一点(不与 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 重合),其他条件不变.求证: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
(3)
在(2)的条件下,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,垂足为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> .设 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 为何值时,四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 是平行四边形,并给予证明.

24.如图,抛物线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 经过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 和点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,与 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 轴的另一个交点为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
(1)
求抛物线的解析式及点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的坐标;
(2)
如图1,若点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 是线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的中点,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 轴上是否存在点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,使得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 是以 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 为斜边的直角三角形?若存在,请求出点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的坐标;若不存在,请说明理由;
(3)
如图2,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 是第一象限内抛物线上的动点,过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 轴,分别交 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 轴于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 中有某个角的度数等于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 度数的2倍时,请求出满足条件的点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的横坐标.

参考答案

1.C

【解析】
先把减法转化为加法,再按照有理数的加法法则运算即可.
解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
故选:C

2.B

【解析】
科学记数法的表示形式为a×10n的形式,其中1≤|a|10n为整数.确定n的值时,要看把原数变成a时,小数点移动了多少位,n的绝对值与小数点移动的位数相同.当原数绝对值≥10时,n是正整数;当原数的绝对值<1时,n是负整数.
解:1100亿=110000000000 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
故选:B

3.A

【解析】
根据概率公式直接求解即可.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 共有 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 个球,其中红球b
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 从中任意摸出一球,摸出红球的概率是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
故选A

4.C

【解析】
根据图示确定几何体的三视图即可得到答案.
由几何体可知,该几何体的三视图为
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
故选C

5.A

【解析】
分别利用求平均数和方差的公式计算,即可求解.
解:平均数为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
方差为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
故选:A

6.D

【解析】
分别根据二次根式乘法法则,完全平方公式,异分母分式加减法法则以及分式除法法则计算出各项结果后,再进行判断即可.
解:A.  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,故此计算错误,不符合题意;
B.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,故此计算错误,不符合题意;
C.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,故此计算错误,不符合题意;
D.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,计算正确,符合题意,
故选:D

7.C

【解析】
根据旋转的性质可得,BC=DC,∠ACE=α,∠A=∠E,则∠B=∠BDC,利用三角形内角和可求得∠B,进而可求得∠E,则可求得答案.
解:∵将 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 绕点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 顺时针旋转得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,且 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
BC=DC,∠ACE=α,∠A=∠E
∴∠
B=∠BDC
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
故选:C

8.A

【解析】
根据一元二次方程的解,以及一元二次方程根与系数的关系即可求解.
解:解:∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 是方程 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的两个实数根,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
故选A

9.D

【解析】
AC的中点M,连接EM <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 由中位线性质可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 再根据 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 可得出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 从而得到FC的长,即可得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的结果.
解:如图所示:取AC的中点M,连接EMDM ,设 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 中点,
EM <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的中位线,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 是菱形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,∠AMD=90°
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
DM= <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
AM= <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
故选:D

10.C

【解析】
根据全等三角形的判定与性质、二次函数的性质等知识逐项判断即可,
解:①项,会员原来购买一个面包需要0.85a元,现在需要a×(1+10%)×0.9=0.99a,则会员购买一个面包比涨价前多花了0.99a-0.85a=0.14a元,故①项正确;
项,如图,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
∵△
ABC是等边三角形,
∴∠
B=∠C=60°
∵∠
B+∠BAD=∠ADE+∠EDC,∠C+∠EDC=∠AED
又∵AD=AE
∴∠
ADE=∠AED
∴∠
B+∠BAD=∠ADE+∠EDC=∠C+∠EDC+∠EDC
∴∠
BAD=∠EDC+∠EDC=2∠EDC,故②项错误;
项,如图,△ABC和△DEFAB=DEAC=DFAM是△ABCBC边上的中线,DN是△DEF的边EF上的中线,AM=DN,即有△ABC≌△DEF,理由如下:
延长AMG点,使得AM=GM,连接GC,延长DNH点,使得DN=NH,连接HF
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
AM是中线,
BM=MC
AM=MG,∠AMB=∠GMC
∴△
AMB≌△GMC
AB=GC
同理可证DE=HF
AM=DN
AG=2AM=2DN=DH
AB=DE
GC=HF
结合AC=DF可得△ACG≌△DFH
∴∠
GAC=∠HDF
同理可证∠GAB=∠HDE
∴∠
BAC=∠GAB+∠GAC=∠HDF+∠HDE=∠EDF
AB=DEAC=DF
∴△
ABC≌△DEF,故③正确;
设原数为x,则新数为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,设原数与新数之差为y
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,变形为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
x等于012355分别代入可知,y随着x的增大而增大,
故④正确;
即正确的有三个,
故选:C

11. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

【解析】
利用提公因式法和公式法即可求解.
解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

12. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

【解析】
反比例函数中k0,则同一象限内yx的增大而减小,由于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,从而得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的取值范围.
解:∵在反比例函数y= <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 中,k0
在同一象限内yx的增大而减小,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
这两个点在同一象限,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

13.      <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>       <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

【解析】
先求出扇形的半径与圆心角,再利用扇形弧长与所围成的圆锥的底面周长的关系求出圆锥的底面半径 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,则可得出答案.
解:∵五边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 为正五边形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,这个扇形的面积为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
设圆锥的底面圆半径为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,则直径为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,则: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
故答案为:  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

14.     3      <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ## <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

【解析】
根据题意列出一元一次方程,函数解析式即可求解.
解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 超过2千克,
设购买了 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 千克,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
设某人的付款金额为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 元,购买量为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 千克,则购买量 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 关于付款金额 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的函数解析式为:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
故答案为:3 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

15.     1      <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

【解析】
根据题意作出图形,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,根据切线的性质,等边对等角,平行线的性质可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,根据 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,进而证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,根据相似三角形的性质列出方程,解方程即可求解.
如图,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 是⊙ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的切线, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,   
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> (舍去)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

16. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

【解析】
根据抛物线求出对称轴 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 轴的交点坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,顶点坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,直线CD的表达式 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,分两种情况讨论:当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 时,当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 时,利用抛物线的性质可知,当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 越大,则抛物线的开口越小,即可求解.
解:抛物线的对称轴为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,故抛物线与 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 轴的交点坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,顶点坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,直线CD的表达式 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 时,且抛物线过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 时,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> (舍去),
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,抛物线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 与线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 只有一个公共点时,
即顶点在直线CD上,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 时,且抛物线过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 时,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
由抛物线的性质可知,当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 越大,则抛物线的开口越小,且抛物线与线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 只有一个公共点,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,且 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
综上所述, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的取值范围为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
故答案为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

17.(1) <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 5
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

【解析】
1)先去绝对值,算负整数指数幂,将特殊角三角函数值代入,再计算即可;
2)直接解二元一次方程组即可.
(1)
原式=2 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> + <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 3
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 5
(2)
整理方程组得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
得:y5-4x
代入得:-5x5
解得:x-1
x-1代入得:y9
则方程组得解为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

18. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

【解析】
过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,则四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 是矩形,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 中,分别表示出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,根据 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 即可求解.
如图,过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,则四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 是矩形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
答:雕像 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的高为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

19.(1)4,2,16,18
(2)18
,理由见解析
(3)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

【解析】
1)根据已知数据找出在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的频数即可求解,根据众数与中位数的定义即可求得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的值;
2)根据中位数的意义求解.
3)根据列表法求概率求解.
(1)
解:将30个数据,从小到大排列如下,
13
1415151515161616161617171718181919192223242627272728303232
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的数据为262727274个,故 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的数据为2830,共2个,故 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
其中 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 出现了5次,次数最多,故 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
15和第16个数据为18,故 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
故答案为:421618
(2)
18
万元
理由:根据中位数为18万元,想让一半左右的营业员都能达到销售目标,你认为月销售额定为18万元合适,
(3)
设第六组两名营业员为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 和第七组的两名营业员 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,列表如下,


A

B

C

D

A


AB

AC

AD

B

BA


BC

BD

C

CA

CB


CD

D

DA

DB

DC



共有12种等可能结果,两名营业员在同一组内的情形有4种可能,
故两名营业员在同一组内的概率为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

20.(1)证明见详解
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

【解析】
1)连接AD,由AB为直径可得ADBC,再根据等腰三角形的三线合一性质即可证明结论.
2)由(1)可得CD=4BC=8,根据 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 即可求得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,进而利用勾股定理即可求得AC,由 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 为⊙ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的直径,得∠BEC=∠ADC=90°,∠C为公共角,可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,根据三角形相似的性质即可求得CE,进而可求解.
(1)
证明:连接AD,如图所示:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 为⊙ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的直径,
ADBC
又∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
三角形ABC为等腰三角形,
ADBC的垂直平分线,
BD=CD
(2)
由(1)可得BD=CD=4
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> BC=2BD=8
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
RtACD中,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
又∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 为⊙ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的直径,
∴∠
BEC=∠ADC=90°,且∠C=∠C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,即 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

21.(1) <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

【解析】
1)根据点C的坐标及点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 点的横坐标,可求得CD的长和点B的纵坐标,进而可求得AC的长,利用勾股定理即可求得AD,进而点A的坐标,进而可求得反比例函数的解析式,进而可求得点B的坐标,再利用待定系数法即可求得一次函数解析式.
2)变形不等式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,即 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,根据数形结合,找出反比例函数图象在一次函数图象上方的部分即可求解.
(1)
解:∵ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,且 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 点的横坐标为1
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,且 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 中,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> A的坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,且点A在反比例函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的图象上,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 反比例函数的解析式为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
B的坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 代入一次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 得,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
一次函数的解析式为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
(2)
由题意得,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,即 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,即 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
只需反比例函数图象在一次函数图象上方即可,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
由图可得当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
不等式的解集为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

22.(1)去年每吨土豆的平均价格是2200
(2)
应将175吨土豆加工成薯片,最大利润为202500

【解析】
1)设去年每吨土豆的平均价格是x元,则第一次采购的平均价格为(x+200)元,第二次采购的平均价格为(x-200)元,根据第二次的采购数量是第一次采购数量的两倍,据此列方程求解;
2)先求出今年所采购的土豆枣数,根据所有采购的土豆必须全部加工完且用时不超过60天,其中加工成薯片的土豆数量不少于加工成淀粉的土豆数量的 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,据此列不等式组求解,然后求出最大利润.
(1)
设去年每吨土豆的平均价格是x元,
由题意得, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
经检验: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 是原分式方程的解,且符合题意,
答:去年每吨土豆的平均价格是2200元;
(2)
由(1)得,今年的土豆数为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ()
设应将m吨土豆加工成薯片,则应将(375m)吨加工成淀粉,
由题意得, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>      
总利润为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>         
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 时,利润最大,最大利润为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> (元).
答:应将175吨土豆加工成薯片,最大利润为202500元.

23.(1)AG=CE
(2)过程见解析
(3)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,证明过程见解析

【解析】
对于(1),根据点EBC的中点,可得答案;
对于(2),取AG=EC,连接EG,说明△BGE是等腰直角三角形,再证明△GAE≌△CEF,可得答案;
对于(3),设BC=x,则BE=kx,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,再利用等腰直角三角形的性质表示EP的长,利用平行四边形的判定得只要EP=FC,即可解决问题.
(1)
解:∵EBC的中点,
BE=CE
GAB的中点,
BG=AG
AG=CE
故答案为:AG=CE
(2)
AG=EC,连接EG
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
四边形ABCD是正方形,
AB=BC,∠B=90°
AG=CE
BG=BE
∴△
BGE是等腰直角三角形,
∴∠
BGE=BEG=45°
∴∠
AGE=135°
四边形ABCD是正方形,
∴∠
BCD=90°
CF是正方形ABCD外角的平分线,
∴∠
DCF=45°
∴∠
ECF=90°+45°=135°
AEEF
∴∠
AEB+∠FEC=90°
∵∠
BAE+∠AEB=90°
∴∠
BAE=CEF
∴△
GAE≌△CEF
AE=EF
(3)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 时,四边形PECF是平行四边形.
如图.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
由(2)得,△GAE≌△CEF
CF=EG
BC=x,则BE=kx
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
EPAC
∴△
PEC是等腰直角三角形,
∴∠
PEC=45°
∴∠
PEC+ECF=180° <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
PE=CF时,四边形PECF是平行四边形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

24.(1) <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> A-10);
(2)
存在E03)或(0-1),使得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 是以 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 为斜边的直角三角形;
(3)2
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

【解析】
1)利用待定系数法解答,即可求解;
2)先根据中点坐标公式可得点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,设点E0m),再根据两点坐标公式可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,再由勾股定理,即可求解;
3)先求出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,再求出直线BC的解析式,然后设点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> CF=a,可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,再分三种情况讨论:若∠PCM=2∠OBC,过点CCFx轴交PM于点F;若∠PMC=2∠OBC;若∠CPM=2∠OBC,过点PPG平分∠CPM,则∠MPG=∠OBC,即可求解.
(1)
解:把点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 和点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 代入,得:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
抛物线的解析式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
y=0,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
A-10);
(2)
解:存在,理由如下:
A-10),点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 是线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 的中点,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
设点E0m),
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 是以 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 为斜边的直角三角形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
整理得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> -1
E的坐标为(03)或(0-1);
(3)
解:∵点B40),C02),
OB=4OC=2
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
设直线BC的解析式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
把点B40),C02)代入得:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
直线BC的解析式为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
设点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> CF=a
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
若∠PCM=2∠OBC,过点CCFx轴交PM于点F,如图甲所示,
∴∠
FCM=∠OBC,即 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
∴∠
PCF=∠FCM
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 轴,
CFPQ
PM=2FM
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> ,解得:解得:a=20(舍去),
P的横坐标为2
若∠PMC=2∠OBC
∵∠
PMC=∠BMN
∴∠
BMN=2∠OBC
∵∠
OBC+∠BMN=90°
∴∠
OBC=30°,与 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 相矛盾,不合题意,舍去;
若∠CPM=2∠OBC,如图乙所示,过点PPG平分∠CPM,则∠MPG=∠OBC
∵∠
PMG=∠BMN
∴△
PMG∽△BMN
∴∠
PGM=∠BNM=90°
∴∠
PGC=90°
PG平分∠CPM,即∠MPG=∠CPG
∴∠
PCM=∠PMC
PC=PM
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a> 0(舍去),
P的横坐标为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
综上所述,点P的横坐标为2 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>            <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/1060/" title="内蒙古" class="c1" target="_blank">内蒙古</a> <a href="/tags/1063/" title="呼和浩特" class="c1" target="_blank">呼和浩特</a>

图甲                                               图乙