1 . 在
中,三边
,
,
所对应的角分别是
,
,
,已知
,
,
成等比数列.若
,数列
满足
前
项和为
,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/32c88abd936125401c8d7e3bc21f4396.png)
____________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.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/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/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/f483e6500ce1b37f5a0174df467b793e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3c65f5e623016ca8ab0a9e91e24775a8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/32c88abd936125401c8d7e3bc21f4396.png)
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解题方法
2 . 如图,圆柱的轴截面为矩形
,点
,
分别在上、下底面圆上,
,
,
,
,则异面直线AM与CN所成角的余弦值为______ .
![](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/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c39cb5abf7b33f248efaa4e50fa2c260.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76e161fd4d515439c00b211b1a830378.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fcd0ced286a0fbc7e4862f8147264277.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f8eeeea1c9652cacce976f8129cf520.png)
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3 . 第二十一届大连国际徒步大会即将召开,现在要从小张、小赵、小李、小罗、小王五名志愿者中选派四人分别从事翻译、安保、礼仪、服务四项不同工作,若小张和小赵只能从事前两项工作,其余三人均能从事这四项工作,若每个工作仅需要一人且每人只能从事一项工作,则不同的选派方案共有______ 种.
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解题方法
4 . 在棱长为2的正方体
中,M为
中点,N为四边形
内一点(含边界),若
平面
,则下列结论正确的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4da530384dd04ac90a025385e8b3c2f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6bed4be4c6552807ba53018fe99ec742.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f239fbcc58fc15535db4b5084c4f7253.png)
A.![]() | B.三棱锥![]() ![]() |
C.点N的轨迹长度为![]() | D.![]() ![]() |
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5 . 某学校组织游戏活动,规则是学生从盒子中有放回的摸球且每次只能摸取1个球,每次摸球结果相互独立,盒中有1分和2分的球若干,摸到1分球的概率为
,摸到2分球的概率为
.
(1)若学生甲摸球2次,其总得分记为
,求随机变量
的分布列与期望;
(2)学生甲、乙各摸5次球,最终得分若相同,则都不获得奖励;若不同,则得分多者获得奖励.已知甲前3次摸球得了6分,求乙获得奖励的概率.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf31876698721a199c7c53c6b320aa86.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4dac452fbb5ef6dd653e7fbbef639484.png)
(1)若学生甲摸球2次,其总得分记为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
(2)学生甲、乙各摸5次球,最终得分若相同,则都不获得奖励;若不同,则得分多者获得奖励.已知甲前3次摸球得了6分,求乙获得奖励的概率.
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2024-06-10更新
|
1302次组卷
|
4卷引用:2024年辽宁省普通高等学校招生全国统一考试(模拟2)数学试题
名校
6 . 在一次数学模考中,从甲、乙两个班各自抽出10个人的成绩,甲班的十个人成绩分别为
,乙班的十个人成绩分别为
.假设这两组数据中位数相同、方差也相同,则把这20个数据合并后( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e481eeec5adda2dd0d839c6118273745.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd877ef4c893b656e492c8818822040c.png)
A.中位数一定不变,方差可能变大 |
B.中位数可能改变,方差可能变大 |
C.中位数一定不变,方差可能变小 |
D.中位数可能改变,方差可能变小 |
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2024-06-10更新
|
1546次组卷
|
7卷引用:辽宁省沈阳市第一二〇中学2023-2024学年高三第十次质量监测(最后一卷)数学试题
辽宁省沈阳市第一二〇中学2023-2024学年高三第十次质量监测(最后一卷)数学试题2024届陕西省榆林市高三三模理数试题2024届福建省厦门第一中学高考模拟(最后一卷)数学试题江苏省扬州中学2024届高三下学期全真模拟数学试卷(已下线)专题4.1统计(2) -重难点突破及混淆易错规避(人教A版2019必修第二册)(已下线)专题03 高一下期末考前必刷卷01(基础卷)-期末考点大串讲(人教A版2019必修第二册)(已下线)统计与成对数据的统计分析-综合测试卷A卷
7 . 函数
(
)经过点
,
图象上距离
轴最近的最高点为
,距离
轴最近的最低点为
,若
为坐标原点,则( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ec89c3bc454d209007c2b29baeeb3b0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/70e1a59013f87211094fdce5078bd839.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8fe413b12ffabfb252121aa2eaa31017.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d275fbb3ee5cd1177ca5a2ceecbbef0f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fea805a29a745227697f6dce0612839b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
A.![]() | B.![]() |
C.![]() ![]() | D.![]() |
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解题方法
8 . 设
,则“
”是
的( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cef33c94375520acf8e2bbaea905757e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b29171d217e72b44bfcdb9509c7543d2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c278321c3100dfab53e34bc70765c007.png)
A.必要而不充分条件 | B.充分而不必要条件 |
C.充分且必要条件 | D.既不充分也不必要条件 |
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9 . 已知
(
为虚数单位),则
的虚部是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ce19fe9954f5f1434cde9b09c6d262a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3a7035cd4adda5d72a9fc9f9fda75995.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e81e59019989b7dc2fb59b037ef6e010.png)
A.![]() | B.![]() | C.1 | D.![]() |
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2024-06-09更新
|
574次组卷
|
2卷引用:辽宁省大连市二十四中学2023-2024学年下学期高三第五次模拟考试数学卷数学
解题方法
10 . 柯西不等式在数学的众多分支中有精彩应用,柯西不等式的n元形式为:设
,
,
不全为0,
不全为0,则
,当且仅当存在一个数k,使得
时,等号成立.
(1)请你写出柯西不等式的二元形式;
(2)设P是棱长为
的正四面体ABCD内的任意一点,点P到四个面的距离分别为
,
,
,
,求
的最小值;
(3)已知无穷正数数列
满足:
①存在
,使得
;
②对任意正整数i、
,均有
.
求证:对任意
,
,恒有
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/50a272adba0f1120109824440f0e252c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ba031aac09bdee5b36549bb6e68bdb5e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/50a272adba0f1120109824440f0e252c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1602c6064af12eed3fd1291f8272d93c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/944ab11422d7221e45aa4cc6d868828b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34039940c47c92f3660e9dc7c27e5961.png)
(1)请你写出柯西不等式的二元形式;
(2)设P是棱长为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf298f00799cbf34b4db26f5f63af92f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5edf900c810371fb21297c15f86d8743.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b31ac1def558351e2e3ed1235c570530.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/342d0252c1b2f7d2a84b5c985d19d547.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8d31659f106fba3c9750661eb0e3c3eb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8dde93376f5d29f8f7d501122759b0ab.png)
(3)已知无穷正数数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76aef4cdcb5af742ce28003b7b6c8c20.png)
①存在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9c24ecf9e59082e563372b12981d03fe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e1b5cbf6a7e19a347e95de7f119094fb.png)
②对任意正整数i、
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8598147874a35becc05e7bf4d90ce096.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a33ac34aa03dc7f0a5faad6dc664ec6.png)
求证:对任意
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f5818ede14d21f6df9ef9c2bfe09286c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1c229aec38946b710076588b7710381c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d191d6de821fbb06a51b5a20112db6de.png)
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