Askor reported: I assumed trigonometric substitution only get the job done if there is out there a sq. root for example ##sqrt x^2 + two ##. No. Trig substitution is useful Should you have the sum or variance of squared terms - they need not be within a sq. root. https://gabletoppak.com/why-white-label-water-bottles-are-a-game-changer-for-your-brand/