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【多选题】
若X与Y是两个不相关的随机变量，且方差都存在，则以下结果正确的是A.
E(X)E(Y)=E(XY)
B.
Cov(X,Y)=0
C.
X 与 Y 一定独立
D.
E(X)E(Y)>E(XY)
E.
E(X)E(Y)
F.
D(X+Y)
G.
D(X+Y)>D(X)+D(Y)
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