名校
解题方法
1 . 设随机变量
满足:
,则
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aa0010cb466163db1349fc1040f6b439.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f62ac49521de4f80430d7c5a6c071feb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f412feb8dcad5599ddfe1d1ceb00ac0b.png)
A.6 | B.27 | C.24 | D.9 |
您最近一年使用:0次
A.6 | B.27 | C.24 | D.9 |