My table of Integrals has the overall situation ##int frac dx x^2+a^2 ## as a 'typical' integral also, not merely the case the place ##a=one##. But I believe this being a Calculus research difficulty it is anticipated with the OP to determine how to do it. Hints got above. Gabletop https://gabletoppak.com/the-benefits-of-switching-to-sustainable-milk-cartons-today/