∫(t-t^2)^2dt interval(0,1) u= t-t^2 du = 1-2tdt dt = du /1-2t ∫(u)^2dt ∫ (u)^2 (du/1-2t) I'm having trouble with the next step. U^2 would become 1/3(u)^3 but how do I deal with the du/1-2t?