My table of Integrals has the overall case ##int frac dx x^2+a^two ## for a 'conventional' integral way too, not merely the situation exactly where ##a=1##. But I do think this currently being a Calculus research trouble it is expected from the OP to figure out how to do it. https://gabletoppak.com/from-plastic-bottles-to-gabletop-cartons-a-step-toward-solving-the-plastic-pollution-crisis/