I am trying to solve a problem I saw in a book about electrostatics. In the book the solution to the integral ∫dz/(z^2+h^2)^(3/2) is z/(h^2*(z^2+h^2)^(1/2) but I can't solve the integral by myself. I have tried integration by substitution but I can't seem to solve it. u=z^2+h^2 du=2zdz dz=du/2z This does not yield a correct result. PS: h is a constant, so you only need to integrate it by dz.