Analytical Applications of Differentiation · Superchallenge problem

$\dfrac{2\sqrt3\,\pi \ell^3}{27}$

$\dfrac{2\sqrt3\,\pi \ell^3}{28}$

$\dfrac{27}{2\sqrt3\,\pi \ell^3}$

$\dfrac{2\sqrt3\,\pi \ell^{4}}{27}$