My table of Integrals has the general situation ##int frac dx x^2+a^2 ## to be a 'typical' integral as well, not merely the situation where by ##a=1##. But I feel this remaining a Calculus research difficulty it is expected on the OP to determine how to get it done. Hints https://gabletoppak.com/aseptic-tetra-pak-vs-non-aseptic-gable-top-choosing-the-right-carton-for-your-needs/