Let fX,Y (x,y) = 1/8 sinxsec2 (y/4) for 0 x , 0 y

Let
fX,Y (x,y) = 1/8 sinxsec2 (y/4)
for 0 ≤ x ≤ π, 0 ≤ y ≤ π
and fX,Y (x,y) = 0 otherwise. Find:
a. The density fX{x) of X.
b. The density fY(y) of Y.
c. P(X < π/2,Y < π/2).