My desk of Integrals has the final case ##int frac dx x^2+a^2 ## to be a 'common' integral also, not just the situation wherever ##a=one##. But I think this getting a Calculus research trouble it is expected from the OP to figure out how to get it done. Hints were https://gabletoppak.com/sustainability-in-action-gable-top-cartons-to-save-our-oceans/