随机变量
的分布列为
且
,则
的值为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b734e8f1546481e3eb4976008a045de.png)
![]() | 0 | 1 | 2 | 3 |
p | 0.1 | a | b | 0.1 |
且
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e958149897dab379db843ae56ac2c08.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c9f2416d1f75a45a314331146550832e.png)
A.-0.2 | B.0.2 | C.0.4 | D.0 |
10-11高二下·吉林延边·期末 查看更多[2]
更新时间:2016-11-30 23:29:39
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【推荐1】已知随机变量
的分布列为下表所示,若
,则
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b734e8f1546481e3eb4976008a045de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d5fccd694d797e3e12d08b623ea18cef.png)
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A.![]() | B.![]() | C.1 | D.![]() |
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【推荐2】有
件产品,其中
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd3304e23f3b0f9569c4140ca89b6498.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ca7d1107389675d32b56ec097464c14.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ca7d1107389675d32b56ec097464c14.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f0fa53c18ada62d61412e6ffb51f84c.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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解题方法
【推荐1】在一次射击训练中,每位士兵最多可射击3次,一旦命中目标,则停止射击,否则一直射击到3次为止.设士兵甲一次射击命中目标的概率为
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【推荐2】某实验测试的规则是:每位学生最多可做实验3次,一旦实验成功,则停止实验,否则一直做到3次为止.设某学生一次实验成功的概率为
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/44fed1be8b7e50f18cb90077d9fce8e4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
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A.![]() | B.![]() | C.![]() | D.![]() |
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