Question

Let Y,X have joint pdf
f xy( x,y)={ 4 ; 0 smaller than equal to x smaller than equal to 1 , 0 smaller than equal to y smaller than equal to 1
and 0 ; otherwise
Find fx ( x) , fy ( y ) ,fx/y ( x/y) ,f y/x ( y/x ) also find E ( X/ Y = y) and E (Y /X = x)