解题方法
1 . 在正四面体
中,M为PA边的中点,过点M作该正四面体外接球的截面,记最大的截面半径为R,最小的截面半径为r,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3bd05adb62374d8ee90daef4a823650c.png)
_________ ;若记该正四面体和其外接球的体积分别为
和
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/caa4c480d031dedac6e81872836d04cc.png)
_________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3bd05adb62374d8ee90daef4a823650c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c4764374bd2fb78e59cd0b283637baeb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c63055a5d6916f99d07fede49120753f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/caa4c480d031dedac6e81872836d04cc.png)
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2卷引用:江西省红色十校2024届高三下学期2月联考数学试卷
解题方法
2 . 如图,在四棱锥
中,四边形
是等腰梯形,
,
,
,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/28/61adb0b3-e3d0-4151-8169-503e6ab54cdd.png?resizew=149)
(1)证明:平面
平面
;
(2)若
,且
,求二面角
的正弦值.
![](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/5f79863ffcfa63117ca6741b20a48e69.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d23382d564259c372ff8e6c99648542.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcd0ced286a0fbc7e4862f8147264277.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cdfa54114f04a75b8c96165b3718ed7f.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/28/61adb0b3-e3d0-4151-8169-503e6ab54cdd.png?resizew=149)
(1)证明:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f04c222223dae9ef27d4c132534d9848.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2f4b4c90faa3f4e43393b38400ff44b1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/37002ada5d194d4d062fa3285d7d9824.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0c5651e38293e0c42a7278af69fa53ae.png)
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2024-03-08更新
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5卷引用:江西省五市九校2024届高三下学期2月开学联考数学试卷
名校
3 . 记
为等差数列
的前
项和,若
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/adf14ebc775db2414a5a960badca8960.png)
______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/78c6bc8b7800aecf6c5c217e12c4be6b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/adf14ebc775db2414a5a960badca8960.png)
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3卷引用:江西省名校教研联盟2024届高三下学期2月开学考试数学试卷
名校
4 . 已知
,且
,则( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/71342cb381e3ea133c1495804b7fa5d2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7474416953bd65d18c1c271a41e115e5.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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3卷引用:江西省名校教研联盟2024届高三下学期2月开学考试数学试卷
名校
解题方法
5 . 已知椭圆
的焦距为2,且
,则
的离心率为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad523e69a1bf925e73a22900b9855df2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d5c5aea75d3f8a2aaeffaabc2b7c1a56.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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3卷引用:江西省名校教研联盟2024届高三下学期2月开学考试数学试卷
解题方法
6 . 在平面直角坐标系中,角
的终边经过点
.
(1)求
,
的值
(2)求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ec73b9782fef85230d8ad4aeb31935ce.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b4179e1ab8705cf19ea7aaf48888843.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4d66c03d4ca06819a6ce7fc8ea6de0f0.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/660eb39d6c87d7828120177f1a2ac9cd.png)
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3卷引用:江西省部分学校2023-2024学年高一下学期开学考试数学试题
江西省部分学校2023-2024学年高一下学期开学考试数学试题陕西省渭南市永兴中学2023-2024学年高一下学期3月月考数学试卷(已下线)第一章三角函数章末十九种常考题型归类(2)-【帮课堂】(北师大版2019必修第二册)
7 . 已知样本
的平均数为
,方差为
,样本
,
,
,
的平均数为
,方差为
,则新样本
,
,
,
,
,
,
,
的方差为______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f1a2f40c3c0853c0d5a4150a9d3fc80.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6f8c4c029e552954bd493b49aeab82d5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8860d9787671b53b1ab68b3d526f5ca.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54015ff5b49e3283901da1291b6b921d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/46f6872ffb1934339c53c2c2282d5889.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/daa5e9bd516f6282483b92cfe6074623.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a1c1904afc801069716e5dca11f51e7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd3304e23f3b0f9569c4140ca89b6498.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61128ab996360a038e6e64d82fcba004.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c814128ea2139e33db94ea590e7c2223.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aec19b68e3add9d5bfcc6269a1855b87.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/daa5e9bd516f6282483b92cfe6074623.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ab84c3fe70da38ccb246fd4a71f9d86.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54015ff5b49e3283901da1291b6b921d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/46f6872ffb1934339c53c2c2282d5889.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/daa5e9bd516f6282483b92cfe6074623.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a1c1904afc801069716e5dca11f51e7.png)
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8 . 现有
张完全相同的卡片,分别写有字母
、
、
、
、
,从中任取一张,看后再放回,再任取一张.甲表示事件“第一次抽取卡片的字母为
”,乙表示事件“第二次抽取卡片的字母为
”,丙表示事件“两次抽取卡片的字母相邻”,丁表示事件“两次抽取卡片的字母不相邻”,则( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d91e07104b699c4012be2d26160976a2.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/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
A.乙与丁相互独立 | B.甲与丙相互独立 |
C.丙与丁相互独立 | D.甲与乙相互独立 |
您最近一年使用:0次
名校
9 . 如图,在四棱锥
中,四边形ABCD是正方形,PA⊥平面ABCD,
,点E,F分别为棱PB,BC的中点.
;
(2)求平面AEF与平面ECD所成二面角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/829f9180ddd9aa1a0ee0dc520f4e0b5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f4486d52b6e410fd7b60428121d96cef.png)
(2)求平面AEF与平面ECD所成二面角的正弦值.
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3卷引用:江西省部分学校2023-2024学年高二下学期开学考试数学试题
10 . 某班共有团员14人,其中男团员8人,女团员6人,并且男、女团员各有一名组长,现从中选6人参加学校的团员座谈会.(用数字做答)
(1)若至少有1名组长当选,求不同的选法总数;
(2)若至多有3名女团员当选,求不同的选法总数;
(3)若既要有组长当选,又要有女团员当选,求不同的选法总数.
(1)若至少有1名组长当选,求不同的选法总数;
(2)若至多有3名女团员当选,求不同的选法总数;
(3)若既要有组长当选,又要有女团员当选,求不同的选法总数.
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6卷引用:江西省部分学校2023-2024学年高二下学期开学考试数学试题
江西省部分学校2023-2024学年高二下学期开学考试数学试题(已下线)6.2.3组合+6.2.4组合数 第三练 能力提升拔高(已下线)高二下学期第一次月考模拟卷(新题型)(导数+计数原理)-2023-2024学年高二数学题型分类归纳讲与练(人教A版2019)山东省临沂市郯城第一中学2023-2024学年高二下学期阶段性检测一数学试卷江苏省泰州中学2023-2024学年高二下学期4月月考数学试题(已下线)6.2.3组合-6.2.4组合数——随堂检测