Working on this problem related to line integrals on vector fields. Help greatly appreciated!

Let F(x, y) = yi - xj x2 + 2/2 j on the set D = {(x, y) | (x, y) # (0,0)}. (a) Show that the condition Q/Ox = OP/dy holds on D, where P(x, y) and Q(x, y) are the i and j components of F, respectively