My Desk of Integrals has the final situation ##int frac dx x^2+a^2 ## like a 'common' integral much too, not just the case where ##a=1##. But I believe this currently being a Calculus homework difficulty it is anticipated in the OP to determine how to get it done. Hints were https://gabletoppak.com/boost-brand-visibility-with-customized-packaged-drinking-water/