My table of Integrals has the overall scenario ##int frac dx x^two+a^2 ## for a 'standard' integral as well, not just the situation in which ##a=one##. But I believe this becoming a Calculus research problem it is expected of the OP to figure out how to get it done. Hints https://gabletoppak.com/elevate-your-brand-with-gable-top-paks-white-label-water-packaging/