来自廖艳芬的问题
设随机变量(X,Y)的联合密度函数为f(x,y)={21/4x^2y,x^2
设随机变量(X,Y)的联合密度函数为f(x,y)={21/4x^2y,x^2
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2020-12-22 06:35
设随机变量(X,Y)的联合密度函数为f(x,y)={21/4x^2y,x^2
设随机变量(X,Y)的联合密度函数为f(x,y)={21/4x^2y,x^2
fx(x)=∫x²~121/(4x²y)dy=(21/4x²)ln(y)|(y:x²~1)=(21/4x²)(-lnx²)fy|x(y|x)=f(x,y)/fx(x)=(1/y)/(-lnx²)=-1/(ylnx²)x=1/2时,密度函数=-1/(yln(1/4...