My table of Integrals has the general situation ##int frac dx x^2+a^2 ## like a 'common' integral much too, not merely the situation where ##a=one##. But I do think this being a Calculus homework issue it is expected from the OP to figure out how to do it. Hints got https://gabletoppak.com/how-gable-top-pak-can-enhance-your-brand-and-customer-experience/