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    Given that the volume (V cm^3) of an expanding sphere is related to its radius (r cm) by the formula v=4/3pir^3, find the rate of change of volume with respect to radius at the instant when the radius is 5 cm.

    If

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    How is dv/dr equal to that?
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    It's just like anything else..multiply by the power and reduce it by 1.
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    (Original post by Zapdos)
    It's just like anything else..multiply by the power and reduce it by 1.
    I though so, I just wanted to make sure.

    So 3r^2 but the 3 is divided by 3 to = 1 right?
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    (Original post by zed963)
    I though so, I just wanted to make sure.

    So 3r^2 but the 3 is divided by 3 to = 1 right?
    3*(4/3) = 4
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    (Original post by zed963)
    Given that the volume (V cm^3) of an expanding sphere is related to its radius (r cm) by the formula v=4/3pir^3, find the rate of change of volume with respect to radius at the instant when the radius is 5 cm.

    If

    Name:  Eqn15.gif
Views: 41
Size:  474 Bytes

    How is dv/dr equal to that?
    Differentiate both side with respect to r
 
 
 
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