Q17 of 78 Page 13

Mark the correct alternative in the following:

Each side of an equilateral triangle is increasing at the rate of 8 cm/hr. The rate of increase of its area when side is 2 cm, is


The area of an equilateral triangle, with side a, is defined as

– (1)


Given that and a=2cm, we have to calculate


Differentiating (1) with respect to t, we get



Substituting the values, we get


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