Question

设随机变量X~(0,1),则Y=2X-1~,),

Answer 1

E(X)=0, D(X)=1

E(Y)=E(2X-1)=2E(X)-1=2*0-1=-1

D(Y)=D(2X-1)=D(2X)=4D(X)=4*1=4

σ(Y)=2

Y~(-1,2)