My table of Integrals has the final case ##int frac dx x^2+a^2 ## to be a 'common' integral as well, not merely the case wherever ##a=one##. But I do think this being a Calculus homework difficulty it is anticipated on the OP to determine how to get it done. Hints https://gabletoppak.com/customized-packaged-drinking-water-with-your-brand-logo/