Askor claimed: I believed trigonometric substitution only get the job done if there is offered a square root for example ##sqrt x^2 + two ##. No. Trig substitution is useful When you've got the sum or variation of squared terms - they needn't be inside a sq. root. Front Gable: https://gabletoppak.com/single-use-plastic-water-bottles-will-not-be-available-in-himachal-from-june-1-use-glass-bottles-and-dispensers-instead/