Q17 of 26 Page 1

The side of an equilateral triangle is increasing at the rate of 2 cm/s. At what rate is its area increasing when the side of the triangle is 20 cm ?

Let A be the area of a triangle and a be the side of the triangle


Given the rate of increase of side = …(1)


We need to find-


As the area of an equilateral triangle is given by –



Differentiating both sides w.r.t t(time) we get-



⇒


As a = 20 cm and using equation 1 we get –



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