名校
解题方法
1 . 在正四面体
中,
,
分别为棱
和
(包括端点)的动点,直线
与平面
,平面
所成角分别为
,
,则( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a5f1641947153c80b987320885a2b57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7abd284f76d9f5769bc189508ce2572b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b5858ee1ce52b251816757257a11c29.png)
A.![]() ![]() ![]() |
B.![]() ![]() ![]() |
C.![]() ![]() |
D.![]() ![]() |
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2 . 将保护区分为面积大小相近的多个区域,用简单随机抽样的方法抽取其中15个区域进行编号,统计抽取到的每个区域的某种水源指标
和区域内该植物分布的数量
,得到数组
.已知
,
,
.
(1)求样本
的样本相关系数;
(2)假设该植物的寿命为随机变量
(
可取任意正整数),研究人员统计大量数据后发现,对于任意的
,寿命为
的样本在寿命超过
的样本里的数量占比与寿命为1的样本在全体样本中的数量占比相同,均为0.1,这种现象被称为“几何分布的无记忆性”.
(i)求
的表达式;
(ii)推导该植物寿命期望
的值(用
表示,
取遍
),并求当
足够大时,
的值.
附:样本相关系数
;当
足够大时,
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/97ea8f47d8d8d9e1832d52b1c7425450.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/02471a4dd55b13c35d8ffaf7c3717c80.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef046c85a536174bec951a53d9f60b33.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/27b562e9bd801d9b060054dbad4cf8da.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f2d9cd101a6f493e68226c889cb9eef1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ac6ba0fbab855b55efd132706206c34.png)
(1)求样本
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/725985b2e0488ae470a1d4c86a746dee.png)
(2)假设该植物的寿命为随机变量
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7399fcd570d1de4057f2059759d18cc9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1b00f4eb7f1bd2ccefbabf0c1dfa8f69.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
(i)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c8647973329cfd3cdf53cc16f24ccac9.png)
(ii)推导该植物寿命期望
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5bf3baba074e8aeb6f3ea117865bbd1b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a4203d1a6c2c250a210b7d5acf02cb4d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5bf3baba074e8aeb6f3ea117865bbd1b.png)
附:样本相关系数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0fff8afd3871b55a19add8c331d18058.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d48723131b516e95795e360967b0a176.png)
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解题方法
3 . 已知椭圆
:
的离心率为
,过点
的直线
交
于点
,
,且当
轴时,
.
(1)求
的方程
(2)记
的左焦点为
,若过
,
,
三点的圆的圆心恰好在
轴上,求直线
的斜率.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7dd54b9df3402ad91e2d34c40efe0c7a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/860884c0017c8bceb5b0edff796c144f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b2a29ba49963134a7232fa8574105fc3.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/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/165a501b2e6a3acc46212e59a166c053.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19efd2f2662ca444c784b69e35f53120.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
(2)记
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.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/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
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4 . 已知正数
,
,
满足
,则( )
![](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/262e895386f3baf3644859395cf7aa0d.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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解题方法
5 . 已知
是两个不共线的向量,
,若
与
是共线向量,则实数
的值为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10814bc3db929e79874befe96cf4e3d4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/71ba7b5660ace151dd2419d967bdadfd.png)
![](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/f0a532e15e232cb4b99a8d4d07c89575.png)
A.![]() | B.6 | C.![]() | D.![]() |
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解题方法
6 . 在数字通信中,信号是由数字0和1组成的序列,且传输相互独立.由于随机因素的干扰,发送的信号0或1有可能被错误地接收为1或0.已知发送0时,收到1的概率为0.1,收到0的概率为0.9;发送1时,收到0的概率为0.3,收到1的概率为0.7.下列说法正确的是( )
A.假设发送信号0和1是等可能的,收到0的概率为0.6 |
B.假设发送信号0和1是等可能的,收到11的概率为0.16 |
C.若发送的信号为111,则收到的信号中恰有两个1的概率为0.147 |
D.假设发送信号0和1是等可能的,已知收到的信号是11,则发送的信号也是11的概率为![]() |
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解题方法
7 . 若集合
,
,则
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9997af540e552afa4a49c57b606b0b40.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a27c4583ff2664f25e115d1c6a7ea814.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4b9b470218359a4a47be9244980489e.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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解题方法
8 . 已知双曲线C:
的左焦点为F,过坐标原点O的直线与C交于A,B两点,且
,
,则C的离心率为_________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3040b6c904477030ecf8ba20b2b18759.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b2208c7e4a34e5c6d1ffb9d7a2efd04d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/741eb4a8eff60c685109bc837be3ce7d.png)
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2卷引用:2024届河北省秦皇岛市部分高中高三二模数学试题
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解题方法
9 . 已知向量
,
,则“
”是“
与
共线”的( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e6ac71e4d5f065b7eed42fa68e3f121.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/39fdc421568268162ea9b657c44e2435.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a25772cf0f28540fea78e3ff69c3278.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/64c5562bd4d1b54424330cb6329cd79d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b45ba716f03748c19b7ce2f99af536ab.png)
A.充分不必要条件 | B.必要不充分条件 |
C.充要条件 | D.既不充分又不必要条件 |
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4卷引用:2024届河北省秦皇岛市部分高中高三二模数学试题
2024届河北省秦皇岛市部分高中高三二模数学试题(已下线)模块二 类型4 相近名词、公式类11个易错高频考点宁夏吴忠市吴忠中学2024届高三下学期第五次模拟理科数学试卷(已下线)2024年高考全国甲卷数学(理)真题变式题6-10
名校
解题方法
10 . 一次知识竞赛中,共有
五道题,参赛人从中抽出三道题回答,每题的分值如下:
答对该试题可得相应的分值,答错不得分,得分不低于60分可以获奖.已知参赛人甲答对
题的概率为
,答对
题的概率均为
,答对E题的概率为
,则甲能获奖的概率为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1d75df9d80ce1e0b7cb50464e293864.png)
分值 | 10 | 20 | 20 | 20 | 30 |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b2a698891d42c70b597f0da4f215f09.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/28855a0db693584aabac1df99dfade3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f89eef3148f2d4d09379767b4af69132.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56d266a04f3dc7483eddbc26c5e487db.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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