My table of Integrals has the general case ##int frac dx x^two+a^2 ## as being a 'regular' integral as well, not merely the situation where by ##a=one##. But I think this getting a Calculus research challenge it is predicted of the OP to figure out how to do it. Hints https://gabletoppak.com/single-use-plastic-water-bottles-will-not-be-available-in-himachal-from-june-1-use-glass-bottles-and-dispensers-instead/