My desk of Integrals has the final scenario ##int frac dx x^two+a^2 ## being a 'common' integral far too, not simply the case the place ##a=one##. But I think this getting a Calculus research problem it is expected from the OP to figure out how to do it. Hints were https://gabletoppak.com/kerala-get-ready-to-say-no-to-plastic-from-october-2/