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【327706】2022年湖南省张家界市中考数学真题

时间:2025-01-20 20:03:01 作者: 字数:15974字
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绝密·启用前

2022年湖南省张家界市中考数学真题

题号

总分

得分





注意事项:

1.答题前填写好自己的姓名、班级、考号等信息

2.请将答案正确填写在答题卡上



评卷人

得分




一、选择题

1. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的倒数是(       
A
2022
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

2.我国是世界人口大国,中央高度重视粮食安全,要求坚决守住1 800 000 000亩耕地红线.将数据1 800 000 000用科学记数法表示为(     
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

3.下列图形中,既是轴对称图形又是中心对称图形的是(     
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

4.下列计算正确的是(     
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

5.把不等式组 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的解集表示在数轴上,下列选项正确的是(     
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

6.某班准备从甲、乙、丙、丁四名同学中选一名最优秀的参加禁毒知识比赛,下表记录了四人3次选拔测试的相关数据:


平均分

95

93

95

94

方差

3.2

3.2

4.8

5.2


根据表中数据,应该选择(     
A
.甲
B
.乙
C
.丙
D
.丁

7.在同一平面直角坐标系中,函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的图像大致是(     
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

8.如图,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 是等边三角形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 内一点, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的面积之和为(     
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

评卷人

得分




二、填空题

9.因式分解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> __

10. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 03这五个数中随机抽取一个数,恰好是无理数的概率是__

11.如图,已知直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> __
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

12.分式方程 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的解是_______

13.我国魏晋时期的数学家赵爽在为天文学著作《周髀算经》作注解时,用4个全等的直角三角形和中间的小正方形拼成一个大正方形,这个图被称为“弦图”,它体现了中国古代数学的成就.如图,已知大正方形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的面积是100,小正方形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的面积是4,那么 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> __
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

14.有一组数据: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> .记 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> __

评卷人

得分




三、解答题

15.计算: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

16.先化简 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,再从123中选一个适当的数代入求值.

17.如图所示的方格纸 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 格长为一个单位长度)中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的顶点坐标分别为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
(1)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 沿 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 轴向左平移5个单位,画出平移后的△ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> (不写作法,但要标出顶点字母);
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 绕点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 顺时针旋转 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,画出旋转后的△ <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> (不写作法,但要标出顶点字母);
(3)
在(2)的条件下,求点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 绕点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 旋转到点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 所经过的路径长(结果保留 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

18.中国“最美扶贫高铁”之一的“张吉怀高铁”开通后,张家界到怀化的运行时间由原来的3.5小时缩短至1小时,运行里程缩短了40千米.已知高铁的平均速度比普通列车的平均速度每小时快200千米,求高铁的平均速度.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

19.如图,菱形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的对角线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 相交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的中点,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的延长线于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
(1)
求证: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
(2)
试判断四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的形状,并写出证明过程.

20.为了有效落实“双减”政策,某校随机抽取部分学生,开展了“书面作业完成时间”问卷调查.根据调查结果,绘制了如下不完整的统计图表:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
频数分布统计表

组别

时间 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> (分钟)

频数

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

6

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

14

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

4


根据统计图表提供的信息解答下列问题:
(1)
频数分布统计表中的 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>    <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>   
(2)
补全频数分布直方图;
(3)
已知该校有1000名学生,估计书面作业完成时间在60分钟以上(含60分钟)的学生有多少人?
(4)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 组有两名男同学、两名女同学,从中随机抽取两名学生了解情况,请用列表或画树状图的方法,求出抽取的两名同学恰好是一男一女的概率.

21.阅读下列材料:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 所对的边分别为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,求证: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
证明:如图1,过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,则:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 中, CD=asinB
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
根据上面的材料解决下列问题:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
(1)
如图2,在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 所对的边分别为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,求证: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
(2)
为了办好湖南省首届旅游发展大会,张家界市积极优化旅游环境.如图3,规划中的一片三角形区域需美化,已知 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 米,求这片区域的面积.(结果保留根号.参考数据: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

22.如图,四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 内接于圆 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 是直径,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的中点,延长 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的延长线于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
(1)
求证: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,求 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的长.

23.如图,已知抛物线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的图像与 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 轴交于 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 两点,与 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 轴交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 为抛物线的顶点.
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
(1)
求抛物线的函数表达式及点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的坐标;
(2)
若四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 为矩形, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> .点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 以每秒1个单位的速度从点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 沿 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 向点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 运动,同时点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 以每秒2个单位的速度从点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 沿 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 向点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 运动,一点到达终点,另一点随之停止.当以 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 为顶点的三角形与 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 相似时,求运动时间 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的值;
(3)
抛物线的对称轴与 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 轴交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 是点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 关于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的对称点,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 轴下方抛物线图像上的动点.若过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 与抛物线只有一个公共点,且分别与线段 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 相交于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,求证: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 为定值.

参考答案

1.D

【解析】
根据倒数定义解答.
解:-2022的倒数是 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
故选:D

2.B

【解析】
直接利用科学记数法的表示形式求解即可.
解:1 800 000  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
故选: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

3.D

【解析】
根据中心对称图形与轴对称图形的概念进行判断即可.
解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> .是轴对称图形,不是中心对称图形,故本选项不符合题意;
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> .不是轴对称图形,是中心对称图形,故本选项不符合题意;
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> .是轴对称图形,不是中心对称图形,故本选项不符合题意;
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> .既是轴对称图形,又是中心对称图形,故本选项符合题意.
故选: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

4.C

【解析】
分别根据同底数幂的乘法运算,合并同类项,积的乘方及完全平方公式进行计算,继而判断即可.
A
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,因此该选项不符合题意;
B
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 不是同类项,因此不能合并,所以该选项不符合题意;
C
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,因此该选项符合题意;
D
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,因此该选项不符合题意;
故选:C

5.D

【解析】
求出不等式组的解集,即可得
解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 不等式组的解集为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
在数轴上表示该不等式组的解集只有D选项符合题意;
故选D
(点晴)
本题考查解一元一次不等式组,解题的关键是掌握解不等式的步骤,能求出不等式组中各不等式的公共解集.

6.A

【解析】
从平均数和方差进行判断,即可得
解:从平均数看,成绩最好的是甲、丙同学,
从方差看,甲、乙方差小,发挥最稳定,
所以要从中选择一名成绩好且发挥稳定的同学参加禁毒知识比赛,应该选择甲,
故选:A
(点晴)
本题考查了平均数和方差,熟悉它们的意义是解题的关键.

7.D

【解析】
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,根据一次函数与反比例函数的性质即可得出答案.
解:当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 时,一次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 经过第一、二、三象限,反比例函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 位于第一、三象限;
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 时,一次函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 经过第一、二、四象限,反比例函数 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 位于第二、四象限;
故选:D

8.C

【解析】
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 绕点B顺时针旋转 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 是等边三角形,再利用勾股定理的逆定理可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,从而求解.

解:将 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 绕点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 顺时针旋转 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 是等边三角形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的面积之和为
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
故选:C

9. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

【解析】
直接利用平方差公式分解即可得

解:原式 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
(点晴)
本题考查了公式法因式分解,熟练掌握因式分解的方法是解本题的关键.

10. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ##0.4

【解析】
先确定无理数的个数,再除以总个数.
解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 是无理数,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> (恰好是无理数) <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

11. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ##35

【解析】
由平行线的性质可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,再由对顶角相等得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,再由三角形的内角和即可求解.
解:如图,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

12.x=-3

【解析】
方程两边都乘xx-2)得出整式方程,求出方程的解,再进行检验即可.
解:方程两边都乘xx-2),得
5
x=3x-2),
解得:x=-3
检验:当x=-3xx-2)≠0
所以x=-3是原方程的解,
故答案为:x=-3

13. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ##0.75

【解析】
根据两个正方形的面积可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,设 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,得到 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,由勾股定理得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,解方程可得x的值,从而解决问题.
解:∵大正方形ABCD的面积是100
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
小正方形EFGH的面积是4
小正方形EFGH的边长为2
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
由勾股定理得, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> (负值舍去),
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

14. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

【解析】
通过探索数字变化的规律进行分析计算.
解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 时,
原式 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
故答案为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

15. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

【解析】
先将各项化简,再算乘法,最后从左往右计算即可得
解:原式 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
(点晴)
本题考查特殊锐角三角函数值,零指数幂,绝对值以及负整数指数幂,解题的关键是掌握特殊锐角三角函数值,零指数幂,绝对值以及负整数指数幂的性质.

16. <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

【解析】
先根据分式的混合运算的法则进行化简后,再根据分式有意义的条件确定 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的值,代入计算即可.
解:原式 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>    
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
因为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 时分式无意义,所以 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 时,原式 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

17.(1)见解析
(2)
见解析
(3)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

【解析】
1)利用平移变换的性质分别作出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的对应点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 即可;
2)利用旋转变换的性质分别作出 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的对应点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 即可;
3)利用弧长公式求解即可.
(1)
解:如图, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 即为所求;
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
(2)
解:如图, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> (即△A2OB2即为所求;
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
(3)
解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

18.296km/h

【解析】
设高铁的速度,再表示出普通列车的速度,然后根据高铁行驶的路程+40=普通列车行驶的路程列出方程,再求出解即可.
解:设高铁的平均速度为xkm/h,则普通列车的平均速度为(x-200)km/h
由题意得:x+40=3.5(x-200)
解得:x=296.
答:高铁的平均速度为296 km/h

19.(1)见解析
(2)
矩形,见解析

【解析】
1)由题意得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,根据平行线的性质得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,用ASA即可证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
2)根据全等三角形的性质得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,即可得四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 为平行四边形,根据菱形的性质得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,即可得.
(1)
证明: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的中点,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 中,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
(2)
四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 为矩形,证明如下:
证明: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 为平行四边形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 为菱形,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 为矩形.

20.(1)188
(2)
见解析
(3)240

(4) <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

【解析】
1)由B组的频数除以所占百分比得出抽取的总人数,即可解决问题;
2)由(1)的结果,补全频数分布直方图即可;
3)由该校学生总人数乘以书面作业完成时间在60分钟以上(含60分钟)的学生所占的比例即可;
4)列表得出共有12种等可能的结果,其中抽取的两名同学恰好是一男一女的结果有8种,再由概率公式求解即可.
(1)
抽取的总人数为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> (人),
m=50×36%=18
n=50-6-14-18-4=8
故答案为:188
(2)
数分布直方图补全如下:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
(3)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> (人 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
答:估计书面作业完成时间在60分钟以上(含60分钟)的学生有240人;
(4)
列表如下:


1

2

1

2

1


(男1,男 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

(男1,女 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

(男1,女 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

2

(男2,男 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>


(男2,女 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

(男2,女 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

1

(女1,男 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

(女1,男 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>


(女1,女 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

2

(女2,男 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

(女2,男 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

(女1,女 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>



由表可知,共有12种等可能的结果,其中抽取的两名同学恰好是一男一女的结果有8种,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 抽取的两名同学恰好是一男一女的概率 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

21.(1)见解析
(2)
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

【解析】
1)作BC边上的高,利用三角函数表示AD后,即可建立关联并求解;
2)作BC边上的高,利用三角函数分别求出AEBC,即可求解.
1证明:如图2,过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
2解:如图3,过点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,在 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 中, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,即 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

22.(1)见解析
(2)1

【解析】
1)连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,根据圆周角推论得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,根据 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的中点得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,用ASA证明 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,即可得;
2)根据题意和全等三角形的性质得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,根据四边形ABCD内接于圆O和角之间的关系得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,即可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,根据相似三角形的性质得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,即可得
(1)
证明:如图所示,连接 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 为直径,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的中点
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 中,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
(2)
解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 四边形 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 内接于圆 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
即: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>

23.(1) <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 顶点为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
(2) <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
(3)见解析

【解析】
1)设二次函数表达式为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,将 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 代入 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,进行计算即可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,根据二次函数的性质即可得;
2)依题意, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 秒后点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的运动距离为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的运动距离为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,分情况讨论:① <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 时, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 时,进行解答即可得;
3根据对称的性质得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,根据直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 与抛物线图像只有一个公共点,即可得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 利用待定系数法可得直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的解析式为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的解析式为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,联立 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,结合已知 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,同理可得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,运用三角函数求出GHGK即可得.
(1)
解:设二次函数表达式为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 代入 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 得:
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
解得, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 抛物线的函数表达式为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 顶点为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
(2)
解:依题意, <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 秒后点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的运动距离为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,则 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的运动距离为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 时,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 时,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
解得 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
综上得,当 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 时,以 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 为顶点的三角形与 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 相似;
(3)
解: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 关于点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的对称点为点 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 与抛物线图像只有一个公共点,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 只有一个实数解,
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
即: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
利用待定系数法可得直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的解析式为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,直线 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的解析式为: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
联立 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> ,结合已知 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
解得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
同理可得: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
则: <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>  <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>
 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a> 的值为 <a href="/tags/55/" title="数学" class="c1" target="_blank">数学</a> <a href="/tags/982/" title="湖南省" class="c1" target="_blank">湖南省</a> <a href="/tags/1043/" title="张家界" class="c1" target="_blank">张家界</a> <a href="/tags/1121/" title="湖南" class="c1" target="_blank">湖南</a>