名校
解题方法
1 . 为庆祝中国共产党成立100周年,某校合唱团组织“唱支山歌给党听”演唱快闪活动.合唱团选出6个人站在第一排,其中甲、乙作为领唱需要站在第一排的正中间,则这6个人的排队方案共有( )
A.24种 | B.48种 | C.120种 | D.240种 |
您最近一年使用:0次
2023-08-15更新
|
488次组卷
|
2卷引用:北京市东直门中学2021-2022学年高二下学期期中考试数学试题
2 . 我国南宋数学家杨辉1261年所著的《详解九章算法》一书里给出了杨辉三角,书中是用汉字来表示的,如图1.研究发现,杨辉三角可以由组合数来表示,如图2.
杨辉三角有很多有趣的性质,如杨辉三角的两个腰上的数字都是1,用组合数表示为
.请写出一条其他的性质,用组合数表示为:______ .从杨辉三角蕴含的规律可知:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/616fbb8c7348bf0f926404bba3df3ce4.png)
______ .
![](https://img.xkw.com/dksih/QBM/editorImg/2023/8/15/7a8aca28-ce0c-498a-bc45-e5b170667a8b.png?resizew=697)
杨辉三角有很多有趣的性质,如杨辉三角的两个腰上的数字都是1,用组合数表示为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7964ea245849a99ef5ad9d30295b1329.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/616fbb8c7348bf0f926404bba3df3ce4.png)
您最近一年使用:0次
3 . 如图,过原点斜率为k的直线与曲线
交于两点
,
,
①k的取值范围是
.
②
.
③当
时,
先减后增且恒为负.
以上结论中所有正确结论的序号是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/12be206d66e65eb92ef08bad8cd8f71d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/12a3efb79f35db8448f3391252ab7d4e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8df332f01628130c084fd46aaca0a4b7.png)
①k的取值范围是
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd90676eb80fa1a5d35bffb087ef0a95.png)
②
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/75b2dbf7259a1d7d48b4626505b998f1.png)
③当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a4356baccfdced22ad483b13700d27b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f5fd6fcd3e83e25540a7f38d2c034fe6.png)
以上结论中所有正确结论的序号是( )
![](https://img.xkw.com/dksih/QBM/editorImg/2023/6/24/7720c496-535d-4d1a-bf7f-a41647a5bf6c.png?resizew=217)
A.① | B.①② | C.①③ | D.②③ |
您最近一年使用:0次
名校
4 . “天问一号”是执行中国首次火星探测任务的探测器,该名称源于屈原长诗《天问》,寓意探求科学真理征途漫漫,追求科技创新永无止境.图(1)是“天问一号”探测器环绕火星的椭圆轨道示意图,火星的球心是椭圆的一个焦点.过椭圆上的点P向火星被椭圆轨道平面截得的大圆作两条切线
,则
就是“天问一号”在点P时对火星的观测角.图(2)所示的Q,R,S,T四个点处,对火星的观测角最大的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2ec8858389f4c3156a946ba8bf0d8a7b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c45a8a837c11c07073da3ff751d70278.png)
A.Q | B.R | C.S | D.T |
您最近一年使用:0次
2023-01-04更新
|
742次组卷
|
7卷引用:北京市西城区北师大二附中2022-2023学年高二上学期12月月考数学试题
名校
解题方法
5 . 如图,在四棱锥
中,四边形
是平行四边形,点F为
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/5/97ce03fd-4ef3-4ff4-9b7e-57a3d437e222.png?resizew=210)
(1)已知点G为线段
的中点,求证:CF∥平面
;
(2)若
,直线
与平面
所成的角为
,再从条件①、条件②、条件③这三个条件中选择几个作为已知,使四棱锥
唯一确定,求:
(ⅰ)直线
到平面
的距离;
(ⅱ)二面角
的余弦值.
条件①:
平面
;
条件②:
;
条件③:平面
平面
.
![](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/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/5/97ce03fd-4ef3-4ff4-9b7e-57a3d437e222.png?resizew=210)
(1)已知点G为线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c4180c271831327644dc83240b715b5.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f83a04565a8ebaa111894b724b0ba266.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f6b86c22b670a8e9f3896f9e8883fbbb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
(ⅰ)直线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20af148464904e21f4374cc8fb886fba.png)
(ⅱ)二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a38a3e226347af68d7b15295342e209.png)
条件①:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
条件②:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a9c3ec174b1ce835cc8737ff6ce57e52.png)
条件③:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4aa9084b8fe0fe05c4388d1f835587b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/852aabd89edffc1b94344ff3f1f31ccd.png)
您最近一年使用:0次
2023-01-04更新
|
951次组卷
|
5卷引用:北京市西城区北师大二附中2022-2023学年高二上学期12月月考数学试题
北京市西城区北师大二附中2022-2023学年高二上学期12月月考数学试题北京市海淀区2022-2023学年高二上学期期末练习数学试题北京市中央民族大学附属中学2022-2023学年高二上学期期末数学试题河南省郑州市第一〇二高级中学2023-2024学年高二上学期10月月考数学试题(已下线)北京市海淀区2023届高三上学期期末练习数学试题变式题16-21
名校
6 . 根据国家高考改革方案,普通高中学业水平等级性考试科目包括政治、历史、地理、物理、化学、生物6门,考生可根据报考高校要求和自身特长,从6门等级性考试科目中自主选择3门科目参加考试,在一个学生选择的三个科目中,若有两个或三个是文史类(政治、历史、地理)科目,则称这个学生选择科目是“偏文”的,若有两个或三个是理工类(物理、化学、生物)科目,则称这个学生选择科目是“偏理”的.为了了解同学们的选课意向,从北京二中高一年级中随机选取了20名同学(记为
,
,2,
,19,20其中
是男生,
是女生),每位同学都各自独立的填写了拟选课程意向表,所选课程统计记录如表:
(1)从上述20名同学中随机选取3名同学,求恰有2名同学选择科目是“偏理”的概率;
(2)从北京二中高一年级中任选两位同学,以频率估计概率,记
为“偏文”女生的人数,求
的分布列和数学期望;
(3)记随机变量
,样本中男生的期望为
,方差为
;女生的期望为
,方差为
,试比较
与
;
与
的大小(只需写出结论).
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/50a272adba0f1120109824440f0e252c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7c45176df950dfe48b8ca7eac08ee349.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f782d70309802445202487eee751cbdd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2dc8086120dd40f8b841f0e3d674fd68.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e266dafb2e8d23f1a572abc1be2a96fd.png)
学生科目 | ![]() | ![]() | ![]() | ![]() | ![]() | ![]() | ![]() | ![]() | ![]() | ![]() | ![]() | ![]() | ![]() | ![]() | ![]() | ![]() | ![]() | ![]() | ![]() | ![]() |
政治 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | |||||||||||
历史 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | ||||||||||
地理 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | ||||||||||
物理 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | |||||||
化学 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | |||||||||||
生物 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
(2)从北京二中高一年级中任选两位同学,以频率估计概率,记
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
(3)记随机变量
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2af47421c0539033d70024966f39835.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0924ce3e7d756f9f222752c9db8fb6af.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a961e29b5b0773f3fdb8cc7e2ceb8094.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/64bad212e1d9b641464ff6178109167e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/517ff073109a22fb321274d83412ebee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0924ce3e7d756f9f222752c9db8fb6af.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/64bad212e1d9b641464ff6178109167e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a961e29b5b0773f3fdb8cc7e2ceb8094.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/517ff073109a22fb321274d83412ebee.png)
您最近一年使用:0次
2023-01-11更新
|
780次组卷
|
6卷引用:北京市第二中学2021-2022学年高二下学期期末数学试题
北京市第二中学2021-2022学年高二下学期期末数学试题北京市海淀区中国人民大学附属中学2023届高三下学期开学摸底练习数学试题北京市人大附中2023届高三下学期2月开学考数学试题(已下线)7.3.2离散型随机变量的方差(分层作业)-【上好课】2022-2023学年高二数学同步备课系列(人教A版2019选择性必修第三册)北京市广渠门中学2024届高三上学期开学考数学试题(已下线)7.3.2 离散型随机变量的方差——课后作业(巩固版)
名校
7 . 已知数列
,
,
,
满足
且
,2,
,
,数列
,
,
,
满足
,2,
,
,其中
,
,2,
,
表示
,
,
,
中与
不相等的项的个数.
(1)数列
,1,2,3,4,请直接写出数列
;
(2)证明:
,2,
,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/713ac1eb0d8cce55d51e62ef4a2b1634.png)
(3)若数列A相邻两项均不相等,且
与A为同一个数列,证明:
,2,
,
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/140b9dbcada4ac2e5fe3cc30009bcd67.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e88093a749c0d46e0ee931ecfaff925.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/07096af3b99fd1cb11c31f19a2c6408e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/84390c669bd7a961e2161106903fa103.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e61e241c6c220b3b4705a8c1a465d7b0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/92e99796887e62d6de33cead5e11c00e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/07096af3b99fd1cb11c31f19a2c6408e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/713ac1eb0d8cce55d51e62ef4a2b1634.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f17923637012a75a01f309379c1909c2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/13423c094861baf4b759b7f3d8c3c226.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/07096af3b99fd1cb11c31f19a2c6408e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a54d5182f8520bfd9e225d835e924bc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/790aeea3e93a2565637c6e0a41bc8ec9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/07096af3b99fd1cb11c31f19a2c6408e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/713ac1eb0d8cce55d51e62ef4a2b1634.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/87d50740801f1809b06dad5152558069.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe0befe2083a287274113203f5ed6f3e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/07096af3b99fd1cb11c31f19a2c6408e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/713ac1eb0d8cce55d51e62ef4a2b1634.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e72adb45c60c2f63b46e65ff787302bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e88093a749c0d46e0ee931ecfaff925.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/07096af3b99fd1cb11c31f19a2c6408e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/668d1dcf486145a68016aab72dc6a4cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/50a272adba0f1120109824440f0e252c.png)
(1)数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f344a2d8d76fad8cbecaffc44f11f907.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
(2)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bfe59c8f17cdb81bf5305909fa137d32.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/07096af3b99fd1cb11c31f19a2c6408e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/713ac1eb0d8cce55d51e62ef4a2b1634.png)
(3)若数列A相邻两项均不相等,且
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c0157ed29461c0c3559684b07c381a0a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/07096af3b99fd1cb11c31f19a2c6408e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/713ac1eb0d8cce55d51e62ef4a2b1634.png)
您最近一年使用:0次
2023-01-11更新
|
437次组卷
|
2卷引用:北京市第二中学2021-2022学年高二下学期期末数学试题
名校
8 . 设函数
,
,若曲线
上存在一点
,使得点
关于原点
的对称点在曲线
上,则
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ec5748527c15e370dcf4230ad2d0e1b5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c829c3f2e2765100d9cf414cc2e6203c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/51c530f4b7491b95acb8ce3eef9aa09d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6a1cfb60420ff7e72c1b9d64f69ae063.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
A.有最小值![]() | B.有最小值![]() |
C.有最大值![]() | D.有最大值![]() |
您最近一年使用:0次
名校
9 . 下列叙述中,
①等差数列
,
为其前n项和,若
,
,则当
时,
最小;
②等差数列
的公差为d,前n项和为
,若
,则
为递增数列;
③等比数列
的前n项和为
,若
,则
有最小项;
④在等差数列
中,记
,若存在
,使得
,则
为递增数列.
正确说法有______ (写出所有正确说法的序号)
①等差数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b134439819d3069da709979cb9b1a991.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5846713aaecbab35ad985cbe9ad7d44a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd6cd3173d146902c5518503888c3b59.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
②等差数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c4ce64685821c3e55c07f151996ca8c3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/846fa57d92d6ad44d6a0cafad1e71ed4.png)
③等比数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ba5c8a6c196890aa7871ea0c82061ea5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/846fa57d92d6ad44d6a0cafad1e71ed4.png)
④在等差数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/134aefab10d3e81e223e9123da5f417e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f29c06a3e9a73e905eb87d71efa201c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fbb50854126e66c09294192ed1db29ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
正确说法有
您最近一年使用:0次
名校
10 . 已知椭圆
:
和双曲线
:
有公共的焦点F1 (−3, 0),F2 (3, 0),点P是C1 与C2在第一象限内的交点, 则下列说法中错误的个数为( )
①椭圆的短轴长为
;
②双曲线的虚轴长为
;
③双曲线C2 的离心率恰好为椭圆C1 离心率的两倍;
④
PF1F2 是一个以PF2为底的等腰三角形.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1241216f3c1cb5e73043dd1037f556d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3dbc0404b2ff77232b480bce5289d7e6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/23f3ffe7abc59e2f65d827c8eab8d36a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/675c20eff35b1d3f37393850e3d7b103.png)
①椭圆的短轴长为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dbff61fe9d4e93d7cc338489d1c99c40.png)
②双曲线的虚轴长为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b91d650c2fc1a741fabdb333b09aeb6.png)
③双曲线C2 的离心率恰好为椭圆C1 离心率的两倍;
④
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce4cba95fc7d4853a243f8e3fb20ce70.png)
A.0 | B.1 | C.2 | D.3 |
您最近一年使用:0次
2023-01-02更新
|
471次组卷
|
2卷引用:北京大学附属中学2022-2023学年高二上学期期末复习数学试题(2)