My Desk of Integrals has the overall situation ##int frac dx x^two+a^2 ## for a 'standard' integral much too, not just the case where by ##a=1##. But I believe this currently being a Calculus research difficulty it is anticipated in the OP to determine how to do it. Hints were https://gabletoppak.com/india-emerges-as-the-largest-plastic-polluter-globally/