Hello, I need help with a very hard integral, I was trying several steps and I tried in the software "derive" but the answer didn't like to me. It is ψ(x,t)= [b^2-(x-vt)^2]^(-2) . I must integrate it with respect to x . Thanks in advance for any help! PD: I tried x-vt = u like the first step du=dx. My teacher adviced to me continue with [b^2-u^2]^(-2) = z but I don't know how to continue in the best way.