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    Can anyone show me how to solve this?
    I am not really sure where to even begin.

    Write a differential equation to express this:

    (a) The rate at which the volume of a sphere changes with radius is proportional to the square of the radius.
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    Differentiate the formula for the volume of a sphere with respect to the radius and then see what you get
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    (Original post by wightsnowolf)
    Differentiate the formula for the volume of a sphere with respect to the radius and then see what you get
    I got 4pir^2, thanks.
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    That's right. So that shows that the rate of change of volume with respect to the radius is proportional to the radius squared, where the constant of proportionality is 4*pi

    Since it will be proportional if V ' = k (r^2)
 
 
 
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Updated: February 2, 2017
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