He looked like a farmer,but he was really a policeman( )disguise.in

He looked like a farmer,but he was really a policeman( )disguise.in

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A really powerful speaker can work( )the feelings of the audience to the fever o

A really powerful speaker can work( )the feelings of the audience to the fever of excitement.up

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设n为正整数,y=yn(x)是微分方程xy'-(n+1)y=0满足条件的解.(I)求yn(x);(Ⅱ)求级数的收敛域及和函数.

设n为正整数,y=yn(x)是微分方程xy'-(n+1)y=0满足条件的解.(I)求yn(x);(Ⅱ)求级数的收敛域及和函数.

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差分方程Δ2yx-yx=5的通解为

差分方程Δ2yx-yx=5的通解为

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设随机变量X,Y相互独立,且X的概率分布为P(X=0)=P(X=2)=1/2,Y的概率密度为(Ⅰ)求P(Y≤EY);(Ⅱ)求Z=X+Y的概率密度。

设随机变量X,Y相互独立,且X的概率分布为P(X=0)=P(X=2)=1/2,Y的概率密度为(Ⅰ)求P(Y≤EY);(Ⅱ)求Z=X+Y的概率密度。

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