問題詳情
20 設一隨機變數（random variable）X，其期望值（mean value） E[X] =1，其均方差（variance） 
。令Y = 3X + 2，則 E[Y2 ] 之值為何？
(A) 36
(B) 34
(C) 25
(D) 18
。令Y = 3X + 2，則 E[Y2 ] 之值為何？(A) 36
(B) 34
(C) 25
(D) 18
參考答案
答案：B
難度：適中0.5
統計：A(0),B(0),C(0),D(0),E(0)
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