名校
1 . 设离散型随机变量
和
的分布列分别为
,
,
,
,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/707ebe32a5013a5104260716fcc740da.png)
,
.定义
,用来刻画
和
的相似程度,设
,
.
(1)若
,
,
,求
;
(2)若
,且
的分布列为
求
的最小值;
(3)对任意与
有相同可能取值的随机变量
,证明:
的值不可能为负数.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a829fdd8ec0f3b7ede883cf2c3e53b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3097e6975627ac7a7fc78326aa3c680d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b945ead3c11ea96273ab77482497c010.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/29d59165a1af56c9a1a39b4836fe1314.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/987292d893f960a7b4915a7023fa41eb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/707ebe32a5013a5104260716fcc740da.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/59e7f7f4284d08f7298e6eb8640bb569.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f7510226e3bef2768c91e7ba164bbd9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a829fdd8ec0f3b7ede883cf2c3e53b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/97b091aa6eaac148b56e9013e17a14ff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20c11f6c800b8e0410674a0c6d307d26.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be604061cf1591f7069472269d4c9719.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/79a18d2bd429301b5478dcd26c572266.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81ca76215449448e07b0ffb35f176ac6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0c1c46297fe3d150d2bdbd6c238dae2.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cc2d3df37e73a8abea815f37dbb3fff5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a829fdd8ec0f3b7ede883cf2c3e53b.png)
![]() | 0 | 1 | 2 |
![]() | ![]() | ![]() | ![]() |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0c1c46297fe3d150d2bdbd6c238dae2.png)
(3)对任意与
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a829fdd8ec0f3b7ede883cf2c3e53b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0c1c46297fe3d150d2bdbd6c238dae2.png)
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名校
2 . 从1,2,3,
,
这
个数中随机抽一个数记为
,再从1,2,
,
中随机抽一个数记为
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a410f3a274456b579cc10d8a32ee012c.png)
______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/daa5e9bd516f6282483b92cfe6074623.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/daa5e9bd516f6282483b92cfe6074623.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a829fdd8ec0f3b7ede883cf2c3e53b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a410f3a274456b579cc10d8a32ee012c.png)
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2024·全国·模拟预测
3 . 已知函数
,若直线
是曲线
与曲线
的公切线,则
的方程为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fb04ceee9bb979906c63a2442c62a056.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/942c2141d01bde6b48210c56a17fc75e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1938c093dd2fbcb752d0eb7a18d143b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
A.![]() | B.![]() |
C.![]() | D.![]() |
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4 . “0,1数列”在通信技术中有着重要应用,它是指各项的值都等于0或1的数列.设
是一个有限“0,1数列”,
表示把
中每个0都变为
,每个1都变为
,所得到的新的“0,1数列”.例如
,则
.设
是一个有限“0,1数列”,定义
.若有限“0,1数列”
,则数列
的所有项之和为__________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/38e3d87be9f706832ef25537d78a201b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/823b15e6dc9fce202c3c57e7d18df0f2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f32df58be46198b2e7a112ed255d8bc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e502eff0c1fe80b2a546ea4af17a9755.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fde81bb00224b2a80ba56c6ce27b94a9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a18722354086c42e62334983fc50eb6a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36091df0a9c71ef14161ba59dbaa4230.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/374de27c75bc2269806d5b44d1518c82.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e645ae0b78ad4ca300e3889ca3f9bcce.png)
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5 . 给定数列
,定义差分运算:
.若数列
满足
,数列
的首项为1,且
,则( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a8062407fffff61da81c84575efd6a27.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/157352244f7facf1f01a5760b5d507b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ee0e7268c7318bde58a99c9702bcba65.png)
A.存在![]() ![]() |
B.![]() |
C.对任意![]() ![]() ![]() |
D.对任意![]() ![]() ![]() |
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解题方法
6 . 甲口袋中装有2个红球和1个黑球,乙口袋中装有1个红球和2个黑球.现从甲、乙两口袋中各任取一个球交换放入另一口袋,称为1次球交换的操作,重复n次这样的操作,记甲口袋中红球的个数为
.
(1)求
;
(2)求
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/93d0f3799612b81e85b87241ec8eee68.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8953501f29bf0b10c063ebe82d980f5d.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/685a18e8694ab2c3243133d8a1988e68.png)
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解题方法
7 . 某大学有甲、乙两个运动场.假设同学们可以任意选择其中一个运动场锻炼,也可选择不锻炼,一天最多锻炼一次,一次只能选择一个运动场.若同学们每次锻炼选择去甲或乙运动场的概率均为
,每次选择相互独立.设王同学在某个假期的三天内去运动场锻炼的次数为
,已知
的分布列如下:(其中
)
(1)记事件
表示王同学假期三天内去运动场锻炼
次
,事件
表示王同学在这三天内去甲运动场锻炼的次数大于去乙运动场锻炼的次数.当
时,试根据全概率公式求
的值;
(2)是否存在实数
,使得
?若存在,求
的值:若不存在,请说明理由;
(3)记
表示事件“甲运动场举办锻炼有奖的抽奖活动”,
表示事件“王同学去甲运动场锻炼”,
.已知王同学在甲运动场举办锻炼有奖的抽奖活动的情况下去甲运动场锻炼的概率,比不举办抽奖活动的情况下去甲运动场锻炼的概率大,证明:
.
![](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/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e362ab25e6f8719efd1b515094b69561.png)
![]() | 0 | 1 | 2 | 3 |
![]() | ![]() | ![]() | ![]() | ![]() |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e819b87f90651d89fcd258c276294e43.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c05b9832b09731a574d4a4adf7448de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1eef5855dd54b607a61027e0b212cd61.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f970f380a12c843bb4a74ff34a15b2ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/108ab49f370919e730e3567070deee65.png)
(2)是否存在实数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1010846eeec6c9da29640f5aa3f8738.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/667df0f959f5626681d6d9aecaf05be1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1010846eeec6c9da29640f5aa3f8738.png)
(3)记
![](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/6efafab9402e42c2212489d7b9408c4b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/12a3dad8b84d4b66d6f4a6f60adcc79e.png)
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解题方法
8 . 某商场周年庆进行大型促销活动,为吸引消费者,特别推出“玩游戏,送礼券”的活动,活动期间在商场消费达到一定金额的人可以参加游戏,游戏规则如下:在一个盒子里放着六枚硬币,其中有三枚正常的硬币,一面印着字,一面印着花;另外三枚硬币是特制的,有两枚双面都印着字,一枚双面都印着花,规定印着字的面为正面,印着花的面为反面.游戏者蒙着眼睛随机从盒子中抽取一枚硬币并连续投掷两次,由工作人员告知投掷的结果,若两次投掷向上的面都是正面,则进入最终挑战,否则游戏结束.最终挑战的方式是进行第三次投掷,有两个方案可供选择:方案一:继续投掷之前抽取的那枚硬币;方案二,不使用之前抽取的硬币,从盒子里剩余的五枚硬币中随机抽取一枚投掷.不管选择方案一还是方案二,如果掷出正面向上,则获奖
(1)求第一次投掷后,向上的面为正面的概率;
(2)若已知某顾客进入了最终挑战 ,求他抽到的硬币是正常硬币的概率;
(3)在已知某顾客进入了最终挑战环节的条件下,试分别计算他选择两种抽奖方案最终获奖的概率,并以此判断应该选择哪种抽奖方案更合适.
(1)求第一次投掷后,向上的面为正面的概率;
(2)若已知某顾客
(3)在已知某顾客进入了最终挑战环节的条件下,试分别计算他选择两种抽奖方案最终获奖的概率,并以此判断应该选择哪种抽奖方案更合适.
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9 . 数学中有许多形状优美、寓意美好的曲线,曲线
就是其中之一(如图).给出下列三个结论:
恰好经过6个整点(即横、纵坐标均为整数的点);
②曲线
上存在有点到原点的距离超过
;
③曲线
所围成的“心形”区域的面积大于3.
其中,所有正确结论的序号是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/811f65c9355c616ef85c547b1fc342bb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
②曲线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf298f00799cbf34b4db26f5f63af92f.png)
③曲线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
其中,所有正确结论的序号是( )
A.① | B.①②③ | C.①② | D.①③ |
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解题方法
10 . 某商城进行促销活动,购买某产品的顾客可以参加一次游戏:在一个不透明箱子中放入红、蓝、黄三种颜色的小球各1个,顾客从中有放回地取出小球,直到取出的小球集齐了三种颜色则停止取球.设顾客停止取球时,取过的小球次数为
,
(1)求
;
(2)设
,数列
,求
的通项公式;
(3)顾客停止取球时,取过的小球次数为
,顾客可以获得对应的
元奖金,其中
,求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/beded6e21d93573807f67478c74e7e24.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3bcfc48f9bc23cc43085bdb910e7a136.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c2984cf03d31b5fa49437a49c393002c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(3)顾客停止取球时,取过的小球次数为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a829fdd8ec0f3b7ede883cf2c3e53b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/98faa95fff49f487cce3a4fdc58bb067.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1d1269b45b8c9bcb0cada085cd86fd88.png)
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