题目内容

设两个随机变量X和Y分别服从N(0,1)、N(0,4)，且ρXY=0.4，则D(X+Y)=,D(X-Y)=__

查看答案

搜索结果不匹配？点我反馈

更多问题

设X～N(0,1)，Y～N(1,2)，且X,Y相互独立，而Z=2X+Y-1，则Z服从________

—Nice to meet you.— _____.

A. Good morning
B. Happy to see you
C. Nice to meet you, too
D. Pleased to see you

- Thank you very much for helping me. - _____.

A. You are welcome
B. It doesn’t matter
C. No need
Don’t say that

My elder brother is _____, because he goes jogging every morning.

A. lazy
B. happy
C. energetic
D. strict