Problem 4: Apply the change of variable to polar coordinates to compute the following integrals R R2-22 (a) In(1 + x2 + y?) dydx, whwre R > 0. Jo 1 - 202 - y2 (b) DV 1 + x2 + 22 dxdy, where D := {(x, y) : x2 + 2