Askor reported: I assumed trigonometric substitution only get the job done if there is out there a square root like ##sqrt x^two + two ##. No. Trig substitution is helpful if you have the sum or change of squared conditions - they don't need to be within a sq. root. https://gabletoppak.com/single-use-plastic-water-bottles-will-not-be-available-in-himachal-from-june-1-use-glass-bottles-and-dispensers-instead/