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搜题/搜资源
【判断题】【消耗次数:1】
设随机变量X,Y相互独立,EX=0,EY=1,DX=1,则E[X(X+Y-2)]=0
①
正确
②
错误
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【判断题】
设随机变量X,Y相互独立,EX=0,EY=1,DX=1,则E[X(X+Y-2)]=1
①
正确
②
错误
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【单选题】
若随机变量X,Y相互独立,EX=EY=0,DX=DY=1,则E(X+Y+1)2=
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设随机变量X~U[0,2],则E(X)=[填空1]
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设相互独立的随机变量X,Y均服从(o,1)上的均匀分布,令Z=X+Y则( ).
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