My table of Integrals has the overall case ##int frac dx x^2+a^2 ## being a 'typical' integral too, not only the case the place ##a=one##. But I feel this remaining a Calculus research problem it is expected in the OP to figure out how to do it. Hints got earlier https://gabletoppak.com/chikkamagaluru-dc-to-declare-mullayyanagiri-hill-station-plastic-free-zone-on-world-earth-day/