My table of Integrals has the general situation ##int frac dx x^two+a^2 ## being a 'normal' integral much too, not merely the situation in which ##a=one##. But I do think this becoming a Calculus homework challenge it is expected of the OP to determine how to get it done. Hints https://gabletoppak.com/kerala-get-ready-to-say-no-to-plastic-from-october-2/