A right circular cylinder is to be designed to hold 750 cm3 of processed milk, and to use a minimal amount of material in its construction. Find the dimensions for the container.

radius = r

height = h
V= πr^2h
750 = πr^2h ----> h = 750/(πr^2)

Surface Area = SA
= 2πr^2 + 2πrh
= 2πr^2 + 2πr(750/(πr^2))
= 2πr^2 + 1500/r
d(SA)/dr = 2πr - 1500/r^2 = 0 for min of SA
r^3 = 1500/(2π) = 750/π
r = (750/π)^(1/3) ---- the cube root of 750/π

You do the button-pushing , also check my arithmetic.