已知随机变量X的分布列为
设
,则
等于_________ .
X | 0 | 1 | 2 |
P |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1f2e03739ad512e233035ce8d39c8d56.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9fbf74fc4ba610d6c4b2283c1cc3a24d.png)
更新时间:2024-05-25 17:09:23
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