My table of Integrals has the overall scenario ##int frac dx x^two+a^two ## for a 'conventional' integral too, not just the case exactly where ##a=1##. But I think this becoming a Calculus homework issue it is expected from the OP to figure out how to do it. Hints were given https://gabletoppak.com/how-gable-top-pak-can-enhance-your-brand-and-customer-experience/