My table of Integrals has the general scenario ##int frac dx x^2+a^2 ## to be a 'conventional' integral also, not simply the situation where by ##a=one##. But I think this getting a Calculus homework dilemma it is anticipated with the OP to determine how to do it. Hints got above. https://gabletoppak.com/why-every-home-should-use-long-lasting-oil-storage-cartons-for-daily-cooking/