题目

4.(单选题) 设X_(1),X_(2),...,X_(n)为来自正态总体N(mu,sigma^2)的样本，则COV(X_(1),X_(2))=A. 0B. 1C. 0.5D. -1

4.(单选题) 设$X_{1},X_{2},\cdots,X_{n}$为来自正态总体$N(\mu,\sigma^{2})$的样本，则$COV(X_{1},X_{2})=$

A. 0

B. 1

C. 0.5

D. -1

题目解答

答案

A. 0