My desk of Integrals has the final circumstance ##int frac dx x^two+a^two ## to be a 'standard' integral as well, not only the case exactly where ##a=1##. But I think this becoming a Calculus homework problem it is expected from the OP to figure out how to make it happen. https://gabletoppak.com/quenching-thirst-building-brands-how-free-water-campaigns-on-gable-top-cartons-create-impactful-brand-awareness/