I have this basic differential equation du/dt=(u^2)*(sin t) This is obviously a separable diff eq. So what i've done is: g(t) = sin t h(u) = u^2 1/(u^2) du = sin t dt Integrating both side.... 1/y = - cos t + c therefor y = - 1/(cos t + c) Which is wrong, there isn't supposed to be a minus sign apparently. I don't know what i've done wrong. Any suggestions? Thanks.