1. The problem statement, all variables and given/known data Calculate the marginal probability distribution function of X given joint pdf f(x,y) = 15x^2 y for 0 <= x <= y <= 1 f(x,y) = 0 otherwise 2. Relevant equations f_x (x) = integral of f(x,y) dy 3. The attempt at a solution I've got no idea what the bounds are for this integral. Also, would it be easier to do it in polar coordinates?