名校
解题方法
1 . 某考试分为笔试和面试两个部分,每个部分的成绩分为A,B,C三个等级,其中A等级得3分、B等级得2分、C等级得1分.甲在笔试中获得A等级、B等级、C等级的概率分别为
,
,
,在面试中获得A等级、B等级、C等级的概率分别为
,
,
,甲笔试的结果和面试的结果相互独立.
(1)求甲在笔试和面试中恰有一次获得A等级的概率;
(2)求甲笔试和面试的得分之和X的分布列与期望.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d33adb74906403b0b00fcbd9fa691d8b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d33adb74906403b0b00fcbd9fa691d8b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d3ffd5c35bba71ea54c28622b6cf505d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f89eef3148f2d4d09379767b4af69132.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4dac452fbb5ef6dd653e7fbbef639484.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5e6486784415f3537c9a13556c05d893.png)
(1)求甲在笔试和面试中恰有一次获得A等级的概率;
(2)求甲笔试和面试的得分之和X的分布列与期望.
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6卷引用:湖南省娄底市第三中学2023-2024学年高二下学期5月月考数学试题
名校
解题方法
2 . 设点集
,从集合
中任取两个不同的点
,
,定义A,
两点间的距离
.
(1)求
中
的点对的个数;
(2)从集合
中任取两个不同的点A,
,用随机变量
表示他们之间的距离
,
①求
的分布列与期望;
②证明:当
足够大时,
.(注:当
足够大时,
)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b3afcb129040d060714f94c0f8c48a04.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ddad3d9fdb5e9951b6a1c31f9a72a71.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f5c6d29b3010fc1dc9cb640ad41d5b97.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8034add7b8011393a866a21479b62f7b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/80ebc8c7e32c1b561a908a36cfa2cbb5.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/32efe4eff75508cb93e828c735dcb695.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c1ffbdfab9dff3ff41ea474f06375032.png)
(2)从集合
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ddad3d9fdb5e9951b6a1c31f9a72a71.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f3bcb4828b16c8e845492f1a53ddd9a9.png)
①求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
②证明:当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b59306134d26d7a35fd18bcdd401faeb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a8eed2b9b1f33517499ef35e044cd104.png)
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2卷引用:湖南省永州市部分学校2023-2024学年高二下学期6月质量检测卷数学试题
名校
解题方法
3 . 如图,圆
与
轴相切于
圆心
在直线
上运动.过点
向圆
作非
轴的切线,切点分别为
两条切线交于点
,设点
的轨迹为曲线
.
的方程;
(2)设
为线段
上一点(不含端点),过
的直线
交曲线
于
两点,且
为
的中点,求
面积的最大值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/380c4f18890b088ef62dcea9b52ec73d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d324b8cc99df14a6418e7d0f7b7d7436.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/433486848d127b7f6dadc40c96d1aec4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/46dc74f006f8d176db51ffe97dd8af90.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/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a74a141b1e4a6b441d17d3ef8db85f75.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9f0009063fe00277645aff1be6e32471.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01c74a907dda6bb7d9d56d009d9df253.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/16e8c7968d57d2a20065a7cb15c9b4eb.png)
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4 . 我们称各项均不相等的正项数列
为“冒泡数列”,对任意冒泡数列,我们按如下步骤进行操作,称为“冒泡操作”
比较
的大小,若
,则交换
的位置;
设前述所有步骤后数列变为
,比较
的大小,若
,则交换
的位置,再继续比较
的大小,若
,再交换
;
设前述所有步骤后数列变为
,比较
的大小,若
,则交换
的位置,再继续比较
的大小,
,直到比较得到
时或者
调整位置至首位时停止比较和交换位置,并进行下一步;
设前述所有步骤后数列变为
,比较
的大小,若
,则交换
的位置,再继续比较
的大小,…,直到比较得到
或者
调整位置至首位时结束操作.
(1)请对数列
5,3,2,9,7作冒泡操作,可表示为
请写出操作结束后得到的数列,并计算交换位置的次数.
(2)对于某个
项冒泡数列
当其完成冒泡操作时的总的交换位置的次数称为其“交换复杂度”,记为![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a802b2e8db56dfb2f367fbbd9c4fe0f.png)
(i)求
的最小值和最大值;
(ii)对于某个
项冒泡数列
及其各项全排列产生的所有不同数列,其交换复杂度的平均数记为
,求
的通项.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be8e9680996fdd9e3a40f62d810e92e8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0aa559d2ca921738d0c6c51f3a036880.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c0158862238e250d2a2598b7d4ecd148.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/43ade3a1d01605706801e238726e55fb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c0158862238e250d2a2598b7d4ecd148.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b0cfe1386cf3dae99d19bf57895c9f67.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a25a0b38f47e113fd4dd76832de690a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/32fee2a3f8c67509707271a3f266a8af.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8784badc8cc600bef381da22d1c628d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/32fee2a3f8c67509707271a3f266a8af.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0525db7ca68c21dfe7a1c4b543b4bee7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9017d3641140e0692048ddbab24d1d6e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0525db7ca68c21dfe7a1c4b543b4bee7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5356eacad97dae1c7e865903171245ce.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ee15a08d7dc7c77ea81607b1f214c092.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1ebefe3e26bef1c8422bfe5a472e0d4a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d9bc971d069730aa97e8734fc884e3ed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1ebefe3e26bef1c8422bfe5a472e0d4a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/240e1ed0392e64705738776ff88b1623.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/07096af3b99fd1cb11c31f19a2c6408e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ae0d398803d6a57b99fbb7994edc767b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4b8d5b6045219ea4527202ab131bb2e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8ed3a0a9f46932f86611d64711d81c7b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cace8ff9678eca7c3386f280c4ed8c9c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/13a67cfcf87e8b88246d7c8e101041bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4a0be03feff9bfb3b2f45a34b6fc2578.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/13a67cfcf87e8b88246d7c8e101041bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d151f7e01f394c4547e8065de1adb689.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5aeba46b164eea610a02251cdbfba03.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
(1)请对数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/569675dd7b2aca2732324f4bea5c02e1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6acd875285006bca9792d6ffbea60191.png)
(2)对于某个
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5be66b629b36c5fe55ff234ad59bffff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a802b2e8db56dfb2f367fbbd9c4fe0f.png)
(i)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/94511620a0ee01ebcc8ac2f3a47ac87d.png)
(ii)对于某个
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf83e20035c3afd6d26ebfd53d768a70.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/de53713b20a2f956c2590ce71fb69c37.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/de53713b20a2f956c2590ce71fb69c37.png)
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5 . 甲、乙两人比赛投篮,每人投三次,进球数多者获胜.设甲进球数为X.乙进球数为Y.已知X的分布列为
乙每次投球进球的概率都为
,设
,
“乙获胜”.
(1)当
时,请根据全概率公式
,求乙获胜的概率;
(2)当两人进球数相同时记为“平局”,设“甲、乙达成平局”的概率为
,当
取最大值时,求
的均值与方差.
X | 0 | 1 | 2 | 3 |
P | ![]() | ![]() | ![]() | ![]() |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/44fed1be8b7e50f18cb90077d9fce8e4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d160df768b3230fe1df4ab590912b6c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9163ebe812708ee5337d62298c2e3363.png)
(1)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f970f380a12c843bb4a74ff34a15b2ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4355a38f9cb11aeec035559c6140c1cb.png)
(2)当两人进球数相同时记为“平局”,设“甲、乙达成平局”的概率为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/060d9334136396f95e9dcd328486f9d2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/060d9334136396f95e9dcd328486f9d2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a829fdd8ec0f3b7ede883cf2c3e53b.png)
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6 . 某大型公司进行了新员工的招聘,共有10000人参与.招聘规则为:前两关中的每一关最多可参与两次测试,只要有一次通过,就自动进入下一关的测试,否则过关失败.若连续通过三关且第三关一次性通过,则成功竞聘,已知各关通过与否相互独立.
(1)若小李在第一关、第二关及第三关通过测试的概率分别为
,求小李成功竞聘的概率
;
(2)统计得10000名竞聘者的得分
,试估计得分在442分以上的竞聘者有多少人.(四舍五人取整)
附:若随机变量
,则
(1)若小李在第一关、第二关及第三关通过测试的概率分别为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b7972c628ff66ac23ec395f5a388e14f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
(2)统计得10000名竞聘者的得分
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9146297289fa8cb88d94336994d0d7a2.png)
附:若随机变量
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/53c1ed67167078ea4f5f1ee53ee14164.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2a2e921bd45eb5aaeefe49703c87573.png)
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2024-06-11更新
|
1115次组卷
|
3卷引用:湖南省长沙市明德中学2023-2024学年高二下学期5月阶段性考试数学试题
名校
解题方法
7 . 二项分布是离散型随机变量重要的概率模型,在生活中被广泛应用.现在我们来研究二项分布的简单性质,若随机变量
.
(1)证明:(ⅰ)
(
,且
),其中
为组合数;
(ⅱ)随机变量
的数学期望
;
(2)一盒中有形状大小相同的4个白球和3个黑球,每次从中摸出一个球且不放回,直到摸到黑球为止,记事件A表示第二次摸球时首次摸到黑球,若将上述试验重复进行10次,记随机变量
表示事件A发生的次数,试探求
的值与随机变量
最有可能发生次数的大小关系.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/870528aa6be6f56bae0eb6b10a765c02.png)
(1)证明:(ⅰ)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2f7ea00923d9f3ccadd6d6186993836a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c9ef0a61e3c701a7cb3a9f9ca3c8dd37.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/53b4b3879d1c6debf0333008f686634e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4fdea830c734212c9831f428918636e8.png)
(ⅱ)随机变量
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2bc4bd923f697154764599eb542e9d96.png)
(2)一盒中有形状大小相同的4个白球和3个黑球,每次从中摸出一个球且不放回,直到摸到黑球为止,记事件A表示第二次摸球时首次摸到黑球,若将上述试验重复进行10次,记随机变量
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a829fdd8ec0f3b7ede883cf2c3e53b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/71701db4b413f2364dbcbd612fbc8a67.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a829fdd8ec0f3b7ede883cf2c3e53b.png)
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名校
解题方法
8 . 对于椭圆
,令
,
,那么在坐标系
中,椭圆经伸缩变换得到了单位圆
,在这样的伸缩变换中,有些几何关系保持不变,例如点、直线、曲线的位置关系以及点分线段的比等等;而有些几何量则等比例变化,例如任何封闭图形在变换后的面积变为原先的
,由此我们可以借助圆的几何性质处理一些椭圆的问题.
(1)在原坐标系中斜率为k的直线l,经过
,
的伸缩变换后斜率变为
,求k与
满足的关系;
(2)设动点P在椭圆
上,过点P作椭圆
的切线,与椭圆
交于点Q,R,再过点Q,R分别作椭圆
的切线交于点S,求点S的轨迹方程;
(3)点
)在椭圆
上,求椭圆上点B,C的坐标,使得△ABC的面积取最大值,并求出该最大值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d8429aec72d26401b12a55b8337261df.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/070cb835e194f9bb99aba9daf58bd2b3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/50443405ab95a95149c68f59f96619de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/863b5f9f0a7c6b7956979a5abc76d8d8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e08c4a230e32f550374a5fa4db5f204.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/848d4055ca831ecde46d1b666ba9e33d.png)
(1)在原坐标系中斜率为k的直线l,经过
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/070cb835e194f9bb99aba9daf58bd2b3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/50443405ab95a95149c68f59f96619de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fbc8ced3660dab6e343773fd9dccebc3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fbc8ced3660dab6e343773fd9dccebc3.png)
(2)设动点P在椭圆
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/841307fdcdbbccacd07b652db535631f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ce30fc0664cca88dbe6d38f32aee81e6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd76519af3c3a098a590ad302acc003b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6aaafb050b24c4e806c480e0665aaa5a.png)
(3)点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad492d5033448d419df9c9b75a71894e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/271e595c257e4c0ade90a9bbbf0e6b0d.png)
您最近一年使用:0次
9 . 如图为英国生物学家高尔顿设计的“高尔顿板”示意图,每一个黑点代表钉在板上的一颗钉子,下方有从左至右依次编号为
的格子(此时钉子层数为
).当小球从板口下落时,它将碰到钉子并有
的概率向左或向右滚下,继续碰至下一层钓子,依次类推落入底部格子.记小球落入格子的编号为
.定义
.
时
的分布列;
(2)证明:
;
(3)改变格子个数(钉子层数相应改变),进行
次实验,第
且
次实验中向格子最大编号为
的高尔顿板中投入
个小球,记所有实验中所有小球落入的格子编号之和为
.已知无交集的独立事件的期望具有累加性,设每次实验、每次投球相互独立,求
关于
的表达式.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dc67b26dd6f40e0630602168cbc3d784.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63c2fcac14983abc2b2429936fe0fbb9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f89eef3148f2d4d09379767b4af69132.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a4f1e3925bda80e8223bf7e431585847.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be604061cf1591f7069472269d4c9719.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
(2)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc5fbb0a0595b5a0153c8b570a6473a0.png)
(3)改变格子个数(钉子层数相应改变),进行
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f6bd9b00a78632a5355fe47b418996ad.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6efe3b837da0d468d85060c9e0e3b639.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/690dd59ae66def0cb99f5bcd3d515e82.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0e77d6f15137ae5d98b0d546672b6f68.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a829fdd8ec0f3b7ede883cf2c3e53b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0b0bd6753e573bfbe6742d08ef6dfe83.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
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解题方法
10 . 京剧被誉为中国文化的瑰宝.每个脸谱都有其独特的象征意义,是京剧中不可或缺的一个组成部分.某商店售卖的京剧脸谱娃娃共有三种款式,有直接购买和盲盒购买两种方式.若直接购买京剧脸谱娃娃,则每个京剧脸谱娃娃售价54元,可选定款式;若盲盒购买京剧脸谱娃娃,则每个盲盒售价27元,盲盒中的一款京剧脸谱娃娃是随机的.
(1)甲采用盲盒购买的方式,每次购买一个盲盒并打开,若买到的京剧脸谱娃娃中出现相同款式,则停止购买.用
表示甲购买盲盒的个数,求
的分布列.
(2)乙计划收集一套京剧脸谱娃娃(三种款式各一个),先购买盲盒,每次购买一个盲盒并打开(乙最多购买3个盲盒),若未集齐一套京剧脸谱娃娃,再直接购买没买到的款式,以购买费用的期望值为决策依据,问乙应购买多少个盲盒?
(1)甲采用盲盒购买的方式,每次购买一个盲盒并打开,若买到的京剧脸谱娃娃中出现相同款式,则停止购买.用
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b734e8f1546481e3eb4976008a045de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b734e8f1546481e3eb4976008a045de.png)
(2)乙计划收集一套京剧脸谱娃娃(三种款式各一个),先购买盲盒,每次购买一个盲盒并打开(乙最多购买3个盲盒),若未集齐一套京剧脸谱娃娃,再直接购买没买到的款式,以购买费用的期望值为决策依据,问乙应购买多少个盲盒?
您最近一年使用:0次
2024-05-08更新
|
494次组卷
|
3卷引用:湖南省长沙市第一中学、长沙市一中城南中学等多校2023-2024学年高二下学期期中考试数学试题