It used to drive me crazy in high school that the derivative of the volume of a sphere (four thirds pi r cubed) is the surface area of a sphere (four pi r squared). No teacher ever addressed this “coincidence.”
But after thinking about it for awhile I realized that if a sphere was growing, the tiniest little instantaneous additional volume being added would be the size of its surface.
That helped me a lot. Maybe it helps you too.
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