已知随机变量
有三个不同的取值,分别是0,1,
,其中
,又
,
,则随机变量
方差的最小值为_______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2fb37ae6ada1e908f4ead466ce03b3a5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/516f5df11797cbd6dc647001dcbe9dca.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c4841a13a2befe940e7657bde95586fd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
21-22高二下·山西临汾·期中 查看更多[2]
更新时间:2022-04-28 22:28:49
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【推荐1】若随机变量
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【推荐2】若随机变量
的分布列如表所示,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e444e9abcefab8ee25c4363957f8369.png)
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【推荐1】小张的公司年会有一小游戏:箱子中有材质和大小完全相同的六个小球,其中三个球标有号码1,两个球标有号码2,一个球标有号码3,有放回的从箱子中取两次球,每次取一个,设第一个球的号码是
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【推荐2】一个口袋中装有大小相同的2个黑球和3个红球,从中摸出两个球,若
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【推荐1】已知随机变量
的分布如下表,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc23dc1709498e8920d7d243213190b2.png)
______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fc23dc1709498e8920d7d243213190b2.png)
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【推荐2】已知某随机变量
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__________ .
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/da32adb27f0b1165ff54ae424d3e8b8e.png)
![](https://img.xkw.com/dksih/QBM/2018/3/29/1912188410044416/1913468594839552/STEM/c91a7791fcb6453a97d357facf7c8f03.png?resizew=106)
且
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fa207f0c279f95e979679c099a7142be.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd353481279871d4c18541586c319c8d.png)
您最近一年使用:0次