My Desk of Integrals has the general situation ##int frac dx x^two+a^two ## as being a 'typical' integral as well, not simply the case exactly where ##a=one##. But I think this currently being a Calculus research challenge it is predicted on the OP to determine how to do it. Hints https://gabletoppak.com/lakes-developed-under-smart-cities-initiative-in-coimbatore-turn-dumping-grounds-for-plastic-waste/