Askor said: I believed trigonometric substitution only work if there is offered a sq. root for example ##sqrt x^two + 2 ##. No. Trig substitution is helpful if you have the sum or variation of squared conditions - they don't need to be inside of a sq. root. In summary, https://gabletoppak.com/how-i-integrated-branding-and-design-with-an-indian-paper-bottle-manufacturer/