2(x, y) = c" f ( yc), (2,4) R \ { (t, 0) |t R}, where f(t) is differentiable for all te R. Show that z satisfies the partial differential cquation dz (x2 y) for all (r, y) E R \ { (t, 0) |t eR}. dz = ryz %3D fil fx + [10 marks]