My table of Integrals has the overall scenario ##int frac dx x^two+a^2 ## for a 'conventional' integral way too, not only the situation where ##a=1##. But I feel this being a Calculus homework challenge it is expected on the OP to determine how to make it happen. Hints got above. https://gabletoppak.com/kerala-get-ready-to-say-no-to-plastic-from-october-2/