My table of Integrals has the general situation ##int frac dx x^2+a^2 ## as a 'normal' integral way too, not simply the situation where by ##a=one##. But I do think this being a Calculus homework issue it is expected in the OP to determine how to get it done. Hints https://gabletoppak.com/kerala-high-court-says-not-to-use-plastic-bottles-at-weddings-in-state/