i dont know how to type the integration symbols
the double integral was Rx X Ry
where x = x, y = y, z = x^2 + y^2
so basically (skipping some steps) the integral becomes: (1 + 4x^2 + 4y^2)^.5
which becomes: r(1 + 4r^2)^.5 when put in polar form
and like i said, i tried 0<feta<2pi and 0<r<3
i got like pi/6 * some quantity. but its supposed to be 4pi
