Askor stated: I assumed trigonometric substitution only work if there is offered a sq. root like ##sqrt x^two + two ##. No. Trig substitution is helpful When you've got the sum or change of squared terms - they needn't be inside of a sq. root. The post traces the history https://gabletoppak.com/why-white-label-water-bottles-are-a-game-changer-for-your-brand/