Askor said: I thought trigonometric substitution only operate if there is on the market a square root including ##sqrt x^two + two ##. No. Trig substitution is useful For those who have the sum or difference of squared conditions - they needn't be inside of a square root. Ad It's https://gabletoppak.com/chikkamagaluru-dc-to-declare-mullayyanagiri-hill-station-plastic-free-zone-on-world-earth-day/