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The sides of an equilateral triangle are increasing at the 2cm per sec.Find the rate at which the area increases when the side is 10cm. |
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Answer» Side of equilateral ∆ = 10cm. AREA of equilateral ∆ = √3 a^2 /4 sq.units. Area of first ∆ = √3 10^2/4 sq. Cm. = 25√3 sq. Cm. Side INCREASED by 2 cm. New side=12cm. Area of second ∆ = √3 12^2 /4 sq. cm. = 36√3 sq. Cm. Increase in area = 36√3 - 25√3=11√3sq.cm.per second Rate of increase in area (% in increase) = 11√3 X 100 / 25√3 = 44% per second |
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