I hope this is in the right place.

Given the joint pdf

f (u, v) = u + v , u > 0, v < 1

determine if U and V are independent

i tried to find f(u) by integrating the joint pdf from 0 to infinity... but my answer comes up to be infinity?

for v, i integrated the joint pdf from negative infinity to 1

is this the only way to find independence? f(u, v) = f(u) * f(v)?