My desk of Integrals has the general situation ##int frac dx x^two+a^2 ## to be a 'conventional' integral way too, not only the case where by ##a=one##. But I think this being a Calculus research trouble it is predicted with the OP to figure out how to get it done. https://gabletoppak.com/how-gable-top-pak-and-paper-bottles-lead-in-sustainable-beverage-packaging/