1 . 设抛掷一枚骰子的点数为随机变量X,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f471d49cf4830d016b6e01ca86815fa.png)
______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f471d49cf4830d016b6e01ca86815fa.png)
您最近一年使用:0次
2 . 随机变量
的分布列如表,若
,则
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b734e8f1546481e3eb4976008a045de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cafb0feaf5b58da826ddefa09a101413.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0e60ff3d4d0abd4a75cc521c0267f92e.png)
0 | 1 | ||
P | a | b |
A.![]() | B.![]() | C.![]() | D.![]() |
您最近一年使用:0次
0 | 1 | ||
P | a | b |
A.![]() | B.![]() | C.![]() | D.![]() |