My table of Integrals has the overall circumstance ##int frac dx x^two+a^2 ## for a 'common' integral as well, not just the situation the place ##a=one##. But I do think this remaining a Calculus homework difficulty it is predicted from the OP to figure out how to do it. Hints https://gabletoppak.com/reducing-microplastics-why-gable-top-cartons-are-better-than-plastic-water-bottles/