11782: 概率论与数理统计第4章 第5题

Memory Limit:128 MB Time Limit:1.000 S
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Submit:3 Solved:0

Description

设有随机变量X、Y,且有E(X)=5,E(Y)=3,D(X)=2,D(Y)=3,E(XY)=0,求D(2X-3Y)的值?

Output

1

Sample Input Copy

0

Sample Output Copy

1