Inverse variation or direct or neither?

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    Inverse Variation
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The discussion centers on the relationship between the volume of a sphere and its radius, defined by the formula V=(4/3)πr³. Participants conclude that while volume does not vary directly with radius (r), it varies directly with the cube of the radius (r³). The constant factor (4/3)π indicates a direct variation with r³, establishing that the volume is a power function of the radius.

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woof123
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the volume of a sphere: V=(4/3)pi*r3

To me it looks like it is direct variation with a power function (V/r3=(4/3)*pi)but i don't think that's what they're looking for
 
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Strictly speaking, neither, as $V$ does not vary directly with $r$.

It does, however, vary directly with $r^3$, as $\dfrac{4}{3}\pi$ is a constant.
 

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