# Math

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What is the rate of change of the volume of a ball (V=(4/3)pi r^3) with respect to the radius when the radius is r=2?

• Math -

LOL, it is the surface area 4 pi r^2
4 pi r^2 dr = dV
or
dV/dr = 4 pi r^2
or
dV/dt = 4 pi r^2 dr/dt

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