My Desk of Integrals has the overall situation ##int frac dx x^two+a^two ## for a 'conventional' integral much too, not simply the situation in which ##a=1##. But I think this currently being a Calculus homework trouble it is expected with the OP to determine how to do it. Hints got https://gabletoppak.com/lakes-developed-under-smart-cities-initiative-in-coimbatore-turn-dumping-grounds-for-plastic-waste/