My table of Integrals has the general case ##int frac dx x^two+a^2 ## like a 'typical' integral far too, not only the situation exactly where ##a=one##. But I do think this getting a Calculus research issue it is expected on the OP to figure out how to do it. Hints https://gabletoppak.com/sustainability-in-action-gable-top-cartons-to-save-our-oceans/