My Desk of Integrals has the final circumstance ##int frac dx x^two+a^two ## as being a 'conventional' integral too, not simply the situation exactly where ##a=one##. But I do think this becoming a Calculus homework trouble it is expected on the OP to figure out how to make it happen. https://gabletoppak.com/water-in-a-sustainable-box-the-future-of-eco-friendly-hydration/