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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解题方法
2 . 如图,在平行四边形
中,
,垂足为P,E为
中点,
·
=32,求
的长;
(2)设|
|=
,|
|=
,
=-
,
=x
+y
,求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bfbad7ad1465d1c4c177e3321e6ed12a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f7239b3f2d88c2e45e17e5de9ae1a332.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/af5f1b06a56fc382feed28e01f1ad102.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20a541b81584a032f571159ea152c85a.png)
(2)设|
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/abcb5d89b04570ceda2c29e11cb27a57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf298f00799cbf34b4db26f5f63af92f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/af5f1b06a56fc382feed28e01f1ad102.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2967337e3fcb228dded64ab0c41a17e0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d3acf551f38311eccdcc325c0d283473.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d83fb9ac8a18e78a4c56da79514b5ccb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f7239b3f2d88c2e45e17e5de9ae1a332.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d021a5c98388463d577675e58068aa7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/af5f1b06a56fc382feed28e01f1ad102.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6f29d5f376c75c41ae6af0c8a8565449.png)
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解题方法
3 . 已知
.
(1)求
的值;
(2)求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/02a2f6d370ed6f1d6582251c6e1bad62.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/850dba25bf0f5f13541bf9b6ec12b84d.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63fe57d4fbae536de2e641d9d349fcf1.png)
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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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5 . 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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6 . 记
内角
的对边分别为
,
,
,已知
,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f23d9f62826855e3caf26d7d4640c1c.png)
(1)求
;
(2)若
,求
的面积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24e0c10fb103930eabd5fa18e8f9bb06.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/071a7e733d466949ac935b4b8ee8d183.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac1143aa4477719481003ec4cc75a565.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f23d9f62826855e3caf26d7d4640c1c.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a7bd466d65409c10c1a1ce60a3c5ea1f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
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解题方法
7 . 某同学参加科技知识网络挑战赛,依次回答从系统题库中随机选择的试题,每题作答完毕后,可以选择继续答题,或者结束比赛,系统计算比赛得分.已知该同学答对每道题的概率均为
,且每次答题相互独立.
(1)已知
,若该同学连续作答30道试题后结束比赛,记该同学答对
道试题的概率为
,则
为何值时,
取得最大值?
(2)已知
,若该同学选择连续作答
道试题后结束比赛的概率为
,
,求该同学恰好答错2道试题的概率.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/44fed1be8b7e50f18cb90077d9fce8e4.png)
(1)已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e74b0aa7a6f6dcab7d9101b98504ae2a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c3f81f2a0196b06fc56a7e8a6463d179.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c3f81f2a0196b06fc56a7e8a6463d179.png)
(2)已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/79a18d2bd429301b5478dcd26c572266.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b3f16923163f3c948a4cc4a713bc1160.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7304f4a3860fb2ce6535b51166d21446.png)
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8 . 为了迎接4月23日“世界图书日”,宁波市将组织中学生进行一次文化知识有奖竞赛,竞赛奖励规则如下,得分在
内的学生获三等奖,得分在
内的学生获二等奖,得分在
内的学生获一等奖,其他学生不得奖.为了解学生对相关知识的掌握情况,随机抽取100名学生的竞赛成绩,并以此为样本绘制了如下样本频率分布直方图.
(1)求
的值;若现从该样本中随机抽取两名学生的竞赛成绩,求这两名学生中恰有一名学生获奖的概率;
(2)若我市所有参赛学生的成绩
近似服从正态分布
,其中
,
为样本平均数的估计值,利用所得正态分布模型解决以下问题:
①若我市共有10000名学生参加了竞赛,试估计参赛学生中成绩超过79分的学生数(结果四舍五入到整数);
②若从所有参赛学生中(参赛学生数大于
随机抽取3名学生进行访谈,设其中竞赛成绩在64分以上的学生数为
,求随机变量
的分布列.
附参考数据:若随机变量
服从正态分布
,则
,
,
.
![](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/3dd615c194ebc63b5219cbbcafd53448.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/6/4/8db1b64f-49d1-4628-afb8-997028fc8d06.png?resizew=274)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
(2)若我市所有参赛学生的成绩
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e84c2c26cbb6b22a415fd0830401aeac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57db59c20e7a352a161bc589d36938e8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1100379a4385b9ce064847bc21760adc.png)
①若我市共有10000名学生参加了竞赛,试估计参赛学生中成绩超过79分的学生数(结果四舍五入到整数);
②若从所有参赛学生中(参赛学生数大于
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b73562b96751d4c368f9ac97f3d88667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b734e8f1546481e3eb4976008a045de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b734e8f1546481e3eb4976008a045de.png)
附参考数据:若随机变量
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e84c2c26cbb6b22a415fd0830401aeac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/256181dd02e41f3a9eadf1de097f472e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0cee36a73c750c9229a4a4f4683cbcd3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8978e75d27c4ccd0b211326ac932e17.png)
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9 . 已知
和
为椭圆
上两点.
(1)求椭圆
的标准方程;
(2)若过点
且斜率为
的直线
交
于另一点
,求
的面积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc039740839539ed44c9b2a77f2ba620.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ff6f19b42df64bcc25192f8e81b9417.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad523e69a1bf925e73a22900b9855df2.png)
(1)求椭圆
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
(2)若过点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f89eef3148f2d4d09379767b4af69132.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a855335176fc36a15017f50a8561348.png)
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名校
解题方法
10 . 已知数列
的前
项和为
.若对每一个
,有且仅有一个
,使得
,则称
为“
数列”.记
,
,称数列
为
的“余项数列”.
(1)若
的前四项依次为0,1,-1,1,试判断
是否为“
数列”,并说明理由;
(2)若
,证明
为“
数列”,并求它的“余项数列”的通项公式.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe229b24e2d56ff6b491725ceae4ff2f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b708c8dcb2d66eb2ce0b3718a9cd924a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1f5c62f6f57cb86e3b2e3719d9f6caa9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10b076b91ddd43ed88bb2127f504005a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1076fbf6b366cb2d5dde6590d3f860c1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe229b24e2d56ff6b491725ceae4ff2f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb32f6df7d866ea22308defee71a45c0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1f5c62f6f57cb86e3b2e3719d9f6caa9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bee4464b3b4eb6e52ee02f095aae84f0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe229b24e2d56ff6b491725ceae4ff2f.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe229b24e2d56ff6b491725ceae4ff2f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe229b24e2d56ff6b491725ceae4ff2f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03b31b0145c37e9be6e4855a0408a4b7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe229b24e2d56ff6b491725ceae4ff2f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
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