My table of Integrals has the final situation ##int frac dx x^two+a^two ## like a 'normal' integral much too, not only the situation the place ##a=1##. But I do think this currently being a Calculus homework difficulty it is predicted in the OP to determine how to do it. Hints https://gabletoppak.com/reducing-microplastics-why-gable-top-cartons-are-better-than-plastic-water-bottles/