SOLUTION: If the radius of a circle is increasing at the rate of 4cm/sec, find the rate of the increase in the area when the radius is 12cm?

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Question 1193217: If the radius of a circle is increasing at the rate of 4cm/sec, find the rate of the increase in the area when the radius is 12cm?
Answer by Alan3354(69443)   (Show Source): You can put this solution on YOUR website!
If the radius of a circle is increasing at the rate of 4cm/sec, find the rate of the increase in the area when the radius is 12cm?
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Area = pi*r^2
dA/dt = 2pi*r*dr/dt
dA/dt = 2pi*12*4 = 96pi cm^2/sec

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