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【334321】2022年北京市高考数学试卷

时间:2025-01-21 18:00:16 作者: 字数:17235字
简介:

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Shape2

绝密·启用前

2022年北京市高考数学试卷

题号

总分

得分






注意事项:

1.答题前填写好自己的姓名、班级、考号等信息

2.请将答案正确填写在答题卡上



评卷人

得分




一、单选题

1.已知全集 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,集合 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,则 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>        
A
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
B
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
C
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
D
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>

2.若复数z满足 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,则 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>        
A
1
B
5
C
7
D
25

3.若直线 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 是圆 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的一条对称轴,则 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>        
A
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
B
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
C
1
D
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>

4.己知函数 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,则对任意实数x,有(       
A
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
B
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
C
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
D
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>

5.已知函数 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,则(       
A
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 上单调递减
B
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 上单调递增
C
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 上单调递减
D
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 上单调递增

6. <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 是公差不为0的无穷等差数列,则“ <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 为递增数列”是“存在正整数 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,当 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 时, <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ”的(       
A
.充分而不必要条件
B
.必要而不充分条件
C
.充分必要条件
D
.既不充分也不必要条件

7.在北京冬奥会上,国家速滑馆“冰丝带”使用高效环保的二氧化碳跨临界直冷制冰技术,为实现绿色冬奥作出了贡献.如图描述了一定条件下二氧化碳所处的状态与T <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的关系,其中T表示温度,单位是KP表示压强,单位是 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> .下列结论中正确的是(       
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
A
.当 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 时,二氧化碳处于液态
B
.当 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 时,二氧化碳处于气态
C
.当 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 时,二氧化碳处于超临界状态
D
.当 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 时,二氧化碳处于超临界状态

8. <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,则 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>        
A
40
B
41
C
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
D
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>

9.已知正三棱锥 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的六条棱长均为6S <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 及其内部的点构成的集合.设集合 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,则T表示的区域的面积为(       
A
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
B
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
C
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
D
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>

10. <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 中, <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> P <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 所在平面内的动点,且 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,则 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的取值范围是(       
A
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
B
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
C
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
D
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>

评卷人

得分




二、填空题

11.函数 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的定义域是_________

12.已知双曲线 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的渐近线方程为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,则 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> __________

13.若函数 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的一个零点为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,则 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ________ <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ________

14.己知数列 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 各项均为正数,其前n项和 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 满足 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> .给出下列四个结论:
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的第2项小于3      <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 为等比数列;
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 为递减数列;             <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 中存在小于 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的项.
其中所有正确结论的序号是__________

评卷人

得分




三、双空题

15.设函数 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 存在最小值,则a的一个取值为________a的最大值为___________

评卷人

得分




四、解答题

16. <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 中, <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
(1)
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
(2)
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,且 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的面积为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,求 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的周长.

17.如图,在三棱柱 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 中,侧面 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 为正方形,平面 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 平面 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> MN分别为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> AC的中点.
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
(1)
求证: <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 平面 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
(2)
再从条件①、条件②这两个条件中选择一个作为已知,求直线AB与平面BMN所成角的正弦值.
条件①: <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
条件②: <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
注:如果选择条件①和条件②分别解答,按第一个解答计分.

18.在校运动会上,只有甲、乙、丙三名同学参加铅球比赛,比赛成绩达到 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 以上(含 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> )的同学将获得优秀奖.为预测获得优秀奖的人数及冠军得主,收集了甲、乙、丙以往的比赛成绩,并整理得到如下数据(单位:m):
甲:9.809.709.559.549.489.429.409359.309.25
乙:9.789.569.519.369.329.23
丙:9.859.659.209.16
假设用频率估计概率,且甲、乙、丙的比赛成绩相互独立.
(1)
估计甲在校运动会铅球比赛中获得优秀奖的概率;
(2)
X是甲、乙、丙在校运动会铅球比赛中获得优秀奖的总人数,估计X的数学期望EX);
(3)
在校运动会铅球比赛中,甲、乙、丙谁获得冠军的概率估计值最大?(结论不要求证明)

19.已知椭圆: <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的一个顶点为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,焦距为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
(1)
求椭圆E的方程;
(2)
过点 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 作斜率为k的直线与椭圆E交于不同的两点BC,直线ABAC分别与x轴交于点MN,当 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 时,求k的值.

20.已知函数 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
(1)
求曲线 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 在点 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 处的切线方程;
(2)
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,讨论函数 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 上的单调性;
(3)
证明:对任意的 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,有 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>

21.已知 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 为有穷整数数列.给定正整数m,若对任意的 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,在Q中存在 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,使得 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,则称Q <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 连续可表数列.
(1)
判断 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 是否为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 连续可表数列?是否为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 连续可表数列?说明理由;
(2)
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 连续可表数列,求证:k的最小值为4
(3)
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 连续可表数列,且 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,求证: <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>

参考答案

1.D

【解析】
利用补集的定义可得正确的选项.
由补集定义可知: <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,即 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
故选:D

2.B

【解析】
利用复数四则运算,先求出 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,再计算复数的模.
由题意有 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,故 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
故选:B

3.A

【解析】
若直线是圆的对称轴,则直线过圆心,将圆心代入直线计算求解.
由题可知圆心为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,因为直线是圆的对称轴,所以圆心在直线上,即 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,解得 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
故选:A

4.C

【解析】
直接代入计算,注意通分不要计算错误.
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,故A错误,C正确;
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,不是常数,故BD错误;
故选:C

5.C

【解析】
化简得出 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,利用余弦型函数的单调性逐项判断可得出合适的选项.
因为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> .
对于A选项,当 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 时, <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,则 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 上单调递增,A错;
对于B选项,当 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 时, <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,则 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 上不单调,B错;
对于C选项,当 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 时, <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,则 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 上单调递减,C对;
对于D选项,当 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 时, <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,则 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 上不单调,D.
故选:C.

6.C

【解析】
设等差数列 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的公差为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,则 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,利用等差数列的通项公式结合充分条件、必要条件的定义判断可得出结论.
设等差数列 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的公差为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,则 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,记 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 为不超过 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的最大整数.
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 为单调递增数列,则 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,则当 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 时, <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ;若 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,则 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 可得 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,取 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,则当 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 时, <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
所以,“ <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 是递增数列” <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> “存在正整数 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,当 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 时, <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ”;
若存在正整数 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,当 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 时, <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,取 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
假设 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,令 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 可得 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,且 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 时, <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,与题设矛盾,假设不成立,则 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,即数列 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 是递增数列.
所以,“ <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 是递增数列” <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> “存在正整数 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,当 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 时, <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> .
所以,“ <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 是递增数列”是“存在正整数 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,当 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 时, <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ”的充分必要条件.
故选:C.

7.D

【解析】
根据 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的关系图可得正确的选项.
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 时, <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,此时二氧化碳处于固态,故A错误.
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 时, <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,此时二氧化碳处于液态,故B错误.
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 时, <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 4非常接近,故此时二氧化碳处于固态,
另一方面, <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 时对应的是非超临界状态,故C错误.
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 时,因 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> , 故此时二氧化碳处于超临界状态,故D正确.
故选:D

8.B

【解析】
利用赋值法可求 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的值.
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,则 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,则 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
故选:B.

9.B

【解析】
求出以 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 为球心,5为半径的球与底面 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的截面圆的半径后可求区域的面积.
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
设顶点 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 在底面上的投影为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,连接 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,则 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 为三角形 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的中心,
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,故 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> .
因为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,故 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的轨迹为以 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 为圆心,1为半径的圆,
而三角形 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 内切圆的圆心为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,半径为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的轨迹圆在三角形 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 内部,故其面积为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
故选:B

10.D

【解析】
依题意建立平面直角坐标系,设 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,表示出 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,根据数量积的坐标表示、辅助角公式及正弦函数的性质计算可得;
解:依题意如图建立平面直角坐标系,则 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
因为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,所以 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 在以 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 为圆心, <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 为半径的圆上运动,
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
所以 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
所以 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,其中 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
因为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,所以 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,即 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
故选:D
             

11. <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>

【解析】
根据偶次方根的被开方数非负、分母不为零得到方程组,解得即可;
解:因为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,所以 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,解得 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
故函数的定义域为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
故答案为: <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>

12. <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>

【解析】
首先可得 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,即可得到双曲线的标准方程,从而得到 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,再跟渐近线方程得到方程,解得即可;
解:对于双曲线 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,所以 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,即双曲线的标准方程为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,又双曲线 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的渐近线方程为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
所以 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,即 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,解得 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
故答案为: <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>

13.     1      <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>

【解析】
先代入零点,求得A的值,再将函数化简为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,代入自变量 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,计算即可.
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,∴ <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
故答案为:1 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>

14.①③④

【解析】
推导出 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,求出 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的值,可判断①;利用反证法可判断②④;利用数列单调性的定义可判断③.
由题意可知, <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 时, <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,可得 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 时,由 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 可得 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,两式作差可得 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
所以, <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,则 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,整理可得 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
因为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,解得 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,①对;
假设数列 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 为等比数列,设其公比为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,则 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,即 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
所以, <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,可得 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,解得 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,不合乎题意,
故数列 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 不是等比数列,②错;
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 时, <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,可得 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,所以,数列 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 为递减数列,③对;
假设对任意的 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,则 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
所以, <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,与假设矛盾,假设不成立,④对.
故答案为:①③④.

15.     0(答案不唯一)     1

【解析】
根据分段函数中的函数 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的单调性进行分类讨论,可知, <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 符合条件, <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 不符合条件, <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 时函数 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 没有最小值,故 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的最小值只能取 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的最小值,根据定义域讨论可知 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>    解得  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> .
解:若 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 时, <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,∴ <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 时,当 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 时, <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 单调递增,当 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 时, <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,故 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 没有最小值,不符合题目要求;
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 时,
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 时, <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 单调递减, <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 时, <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
解得 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
综上可得 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
故答案为:0(答案不唯一),1

16.(1) <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
(2)
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>

【解析】
1)利用二倍角的正弦公式化简可得 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的值,结合角 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的取值范围可求得角 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的值;
2)利用三角形的面积公式可求得 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的值,由余弦定理可求得 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的值,即可求得 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的周长.
(1)
解:因为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,则 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,由已知可得 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
可得 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,因此, <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> .
(2)
解:由三角形的面积公式可得 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,解得 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> .
由余弦定理可得 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
所以, <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的周长为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> .

17.(1)见解析
(2)
见解析

【解析】
1)取 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的中点为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,连接 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,可证平面 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 平面 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,从而可证 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 平面 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> .
2)选①②均可证明 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 平面 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,从而可建立如图所示的空间直角坐标系,利用空间向量可求线面角的正弦值.
(1)
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的中点为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,连接 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
由三棱柱 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 可得四边形 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 为平行四边形,
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,则 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 平面 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 平面 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,故 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 平面 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,则 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,同理可得 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 平面 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 平面 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
故平面 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 平面 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,而 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 平面 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,故 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 平面 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
(2)
因为侧面 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 为正方形,故 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 平面 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,平面 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 平面 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
平面 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 平面 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,故 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 平面 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
因为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,故 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 平面 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
因为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 平面 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,故 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
若选①,则 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,而 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 平面 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,而 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 平面 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,故 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
所以 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,而 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,故 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 平面 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
故可建立如所示的空间直角坐标系,则 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
设平面 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的法向量为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,从而 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,取 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,则 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
设直线 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 与平面 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 所成的角为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,则
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> .
若选②,因为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,故 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 平面 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,而 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 平面 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,而 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,故 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,故 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
所以 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,故 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,故 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 平面 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
故可建立如所示的空间直角坐标系,则 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
设平面 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的法向量为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,从而 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,取 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,则 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
设直线 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 与平面 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 所成的角为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,则
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> .
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>

18.(1)0.4
(2)
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
(3)


【解析】
(1)
       由频率估计概率即可
(2)
       求解得X的分布列,即可计算出X的数学期望.
(3)
       计算出各自获得最高成绩的概率,再根据其各自的最高成绩可判断丙夺冠的概率估计值最大.
(1)
由频率估计概率可得
甲获得优秀的概率为0.4,乙获得优秀的概率为0.5,丙获得优秀的概率为0.5
故答案为0.4
(2)
设甲获得优秀为事件A1,乙获得优秀为事件A2,丙获得优秀为事件A3
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>

 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>


 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>

 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>


 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> .
X的分布列为

X

0

1

2

3

P

 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>

 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>

 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>

 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>


 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
(3)
丙夺冠概率估计值最大.
因为铅球比赛无论比赛几次就取最高成绩.比赛一次,丙获得9.85的概率为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,甲获得9.80的概率为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,乙获得9.78的概率为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> .并且丙的最高成绩是所有成绩中最高的,比赛次数越多,对丙越有利.

19.(1) <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
(2)
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>

【解析】
1)依题意可得 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,即可求出 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,从而求出椭圆方程;
2)首先表示出直线方程,设 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,联立直线与椭圆方程,消元列出韦达定理,由直线 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的方程,表示出 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,根据 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 得到方程,解得即可;
(1)
解:依题意可得 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,又 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
所以 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,所以椭圆方程为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
(2)
解:依题意过点 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的直线为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,设 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,不妨令 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,消去 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 整理得 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
所以 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,解得 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
所以 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
直线 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的方程为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,令 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,解得 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
直线 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 的方程为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,令 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,解得 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
所以 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
所以 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
整理得 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,解得 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>

20.(1) <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
(2)
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 上单调递增.
(3)
证明见解析

【解析】
1)先求出切点坐标,在由导数求得切线斜率,即得切线方程;
2)在求一次导数无法判断的情况下,构造新的函数,再求一次导数,问题即得解;
3)令 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,即证 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,由第二问结论可知 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> [0,+∞)上单调递增,即得证.
(1)
解:因为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,所以 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
即切点坐标为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
切线斜率 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
切线方程为: <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
(2)
解:因为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>        
所以 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 上单调递增,
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 上恒成立,
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 上单调递增.
(3)
解:原不等式等价于 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
即证 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
由(2)知 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 上单调递增,
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 上单调递增,又因为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,所以命题得证.

21.(1) <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 连续可表数列;不是 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 连续可表数列.
(2)
证明见解析.
(3)
证明见解析.

【解析】
1)直接利用定义验证即可;
2)先考虑 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 不符合,再列举一个 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 合题即可;
3 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 时,根据和的个数易得显然不行,再讨论 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 时,由 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 可知里面必然有负数,再确定负数只能是 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,然后分类讨论验证不行即可.
(1)
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,所以 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 连续可表数列;易知,不存在 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 使得 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,所以 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 不是 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 连续可表数列.
(2)
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,设为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,则至多 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 6个数字,没有 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 个,矛盾;
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,数列 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,满足 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
(3)
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,若 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 最多有 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 种,若 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,最多有 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 种,所以最多有 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 种,
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,则 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 至多可表 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 个数,矛盾,
从而若 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> , <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 至多可表 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 个数,
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,所以其中有负的,从而 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 可表1~20及那个负数(恰 21个),这表明 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 中仅一个负的,没有0,且这个负的在 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 中绝对值最小,同时 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 中没有两数相同,设那个负数为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
则所有数之和 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>  <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,再考虑排序,排序中不能有和相同,否则不足 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 个,
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> (仅一种方式),
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 2相邻,
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 不在两端, <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 形式,
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,则 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> (有2种结果相同,方式矛盾),
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> , 同理 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,故 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 在一端,不妨为 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 形式,
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> , <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> (有2种结果相同,矛盾), <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> 同理不行,
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,则 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> (有2种结果相同,矛盾),从而 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
由于 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,由表法唯一知3,4不相邻,
故只能 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,①或 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,②
2种情形,
对①: <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,矛盾,
对②: <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a> ,也矛盾,综上 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>
 <a href="/tags/54/" title="试卷" class="c1" target="_blank">试卷</a> <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/56/" title="北京" class="c1" target="_blank">北京</a> <a href="/tags/217/" title="北京市" class="c1" target="_blank">北京市</a>


Shape4 3页,总1