1 . 某市高一年级数学期末考试,满分为100分,为做好分析评价工作,现从中随机抽取100名学生成绩,经统计,这批学生的成绩全部介于40和100之间,将数据按照
,
,
,
,
,
分成6组,制成如图所示的频率直方图.
(2)若成绩在
的为A等级,
的为B等级,其他为C等级,
①在这100名学生中用分层抽样的方法在A,B,C三个等级中抽取25人,求从B等级中抽取的人数.
②以样本估计总体,用频率代替概率,从该市所有参加考试的高一年级学生中随机抽取3人,求至少有一人为B等级的概率.(注:当总体数比较大时,不放回抽取可视为有放回抽取)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/64fc138be9688253cbdeae2808eb74ae.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/486c7705dbd7b7b9ec5dd17b4891088b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ea146d8ec45e63ad14683fd31064de66.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e77699e3d1ddc6e698a640573a7ef787.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d90faf85d1548242098a6fe3accd84f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef1a32a9f2b04fc931c6a0da0b7485e2.png)
(2)若成绩在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef1a32a9f2b04fc931c6a0da0b7485e2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c391d1ca31fa5f2b6de158bb3b47791.png)
①在这100名学生中用分层抽样的方法在A,B,C三个等级中抽取25人,求从B等级中抽取的人数.
②以样本估计总体,用频率代替概率,从该市所有参加考试的高一年级学生中随机抽取3人,求至少有一人为B等级的概率.(注:当总体数比较大时,不放回抽取可视为有放回抽取)
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2 . 在
中,已知
,
,
,则
角的度数为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fadd2e6f0aa16c2c466c904474ffc79c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5742b2684d00be50a66e01c9acb6b51f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/59e29b822cda1ba926e96368094fa1a7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
A.![]() | B.![]() | C.![]() ![]() | D.![]() |
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解题方法
3 . 同时抛掷两枚质地均匀的骰子,观察向上的点数,设事件
“第一枚向上点数为奇数”,事件
“第二枚向上点数为偶数”,事件
“两枚骰子向上点数之和为8”,事件
“两枚骰子向上点数之积为奇数”,则( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5f1e5d29de6e4d72bfed62d9c14dde5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1f9fabbbe61a759e52ec975215e2e7c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/26308ea6d8f321d27acbd7f9b131f9f1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a6d85799453899836bc34ad276ec80e.png)
A.![]() | B.A与C相互独立 | C.B与D互斥 | D.B与D相互独立 |
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解题方法
4 . 已知函数f(x)=
sin x+m cos x
(1)若函数 f(x) 的图象关于直线x=
轴对称,求实数m的值.
(2)已知锐角△ABC的角A,B,C对边分别是a,b,c,c=
且当m=1时满足 f(A)= ![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca69890d870ac9a79fe891ff57396e37.png)
(i)若∠BCA的角平分线交边AB于D,且CD=
,求△ABC的周长;
(ii)求
的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a7ffe8515ff6183c1c7775dc6f94bdb8.png)
(1)若函数 f(x) 的图象关于直线x=
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c67d01e61dc0042e67b5e8ec8e727c22.png)
(2)已知锐角△ABC的角A,B,C对边分别是a,b,c,c=
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a7ffe8515ff6183c1c7775dc6f94bdb8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca69890d870ac9a79fe891ff57396e37.png)
(i)若∠BCA的角平分线交边AB于D,且CD=
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8d5989c84e320b504511f23eeb6e7357.png)
(ii)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/47d808aaeab0898dc2f2234d4f7d4b7a.png)
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解题方法
5 . 已知
,
,
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/29c6b242096be9b5f75daf95be75c232.png)
______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d0a2c3e186a1c1887b3f95a3c809fa9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/33b8c32b7db467349d65316dc7667411.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/45f0ee968f9a247871a54e505fbd111b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/29c6b242096be9b5f75daf95be75c232.png)
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6 . 如图,在四棱锥
中,底面
为正方形,
在棱
上且
侧面
,
,垂足为
.
平面
;
(2)若平面
与直线
交于点
,证明:
;
(3)侧面
为等边三角形时,求二面角
的平面角
的正切值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7d0edb1508fc95765f3bb316bcb5252d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80f747eb5b2d21c9de962cbfd4ec4bb7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7713c13736076f1fe2c139bb4a4b6d6e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f3e126c16032892966489053f44b9048.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
(2)若平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/176385d91d5e29324fce4a932eff6a79.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bb6329d83756f7779c4982db16c12cbd.png)
(3)侧面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/053af8641980763a7f0e77beefe0712d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8505aaf8a003faa6051bbd1edaa5ee91.png)
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解题方法
7 . 向量
与
不共线,
,
(
),若
与
共线,则
应满足( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/64c5562bd4d1b54424330cb6329cd79d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b45ba716f03748c19b7ce2f99af536ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42ac56c50229b941ed1ac7c653a3687c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/52ebf3930a3a995c05a833765866272a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e3c2709edf306025d40299aaf455aec1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/abcb5d89b04570ceda2c29e11cb27a57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/af5f1b06a56fc382feed28e01f1ad102.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef3e9eb0c4bd9c899886668229c4c947.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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8 . 5和45的等比中项是_________________ .
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名校
解题方法
9 . “绿水青山,就是金山银山”,随着我国的生态环境越来越好,外出旅游的人越来越多.现有两位游客慕名来江苏旅游,他们分别从“太湖鼋头渚、苏州拙政园、镇江金山寺、常州恐龙园、南京夫子庙、扬州瘦西湖”这6个景点中随机选择1个景点游玩.记事件
为“两位游客中至少有一人选择太湖鼋头渚”,事件
为“两位游客选择的景点不同”,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15003d39600a1cb5a33af76246bbc78a.png)
_____________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15003d39600a1cb5a33af76246bbc78a.png)
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名校
解题方法
10 . 第一组样本数据
,第二组样本数据
,其中
则( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1fe1c31a81f198c443e71b83ca662939.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/351e486570290f0433ace7d0ecf2d473.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0249c0a6838ecd07df185a1815780579.png)
A.第二组样本数据的样本平均数小于第一组样本数据的样本平均数的2倍 |
B.第二组样本数据的中位数大于第一组样本数据的中位数的2倍 |
C.第二组样本数据的样本标准差等于第一组样本数据的样本标准差的2倍 |
D.第二组样本数据的样本极差等于第一组样本数据的样本极差的2倍 |
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