Askor reported: I assumed trigonometric substitution only get the job done if there is obtainable a square root for example ##sqrt x^two + 2 ##. No. Trig substitution is helpful When you've got the sum or variation of squared conditions - they needn't be within a sq. root. (Sporting activities) https://gabletoppak.com/why-i-switched-to-water-in-a-sustainable-box/