设随机变量X与Y相互独立,且D(X)=1,D(Y)=2,求D(X-Y).
设随机变量X与Y相互独立,且D(X)=1,D(Y)=2,求D(X-Y).
【正确答案】:D(X-Y)=D(X)+D(Y=1+2=3.
Top