My table of Integrals has the overall situation ##int frac dx x^two+a^two ## like a 'common' integral as well, not only the case the place ##a=one##. But I believe this being a Calculus research problem it is anticipated with the OP to determine how to make it happen. Hints got https://gabletoppak.com/gabletop-pak-the-ideal-packaging-solution-for-dairy-products/