A stone dropped into a still pond sends out a circular ripple whose radius increases at a constant rate of 4ft/s. How rapidly is the area enclosed by the ripple increasing at the end of 12s?
Please help me i will be forever grateful.
Please help me i will be forever grateful.
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A = pi*r^2
dA/dt = 2pi*r(dr/dt)
When t = 12 s, r = 48 ft
dA/dt = 2pi*48*4 = 384pi ft^2/s
dA/dt = 2pi*r(dr/dt)
When t = 12 s, r = 48 ft
dA/dt = 2pi*48*4 = 384pi ft^2/s