Question

A cylindrical can has a volume of 2in^(3). Express the surface area of the can as a function of its radius,r.

Answer 1

`V=2 \text{ in}^3\\ A=2\pi r (r+h)\\ h=?\\\\ V=\pi r^2h=2\\ \pi r^2h=2\\ h=(2)/(\pi r^2)\\ A=2\pi r\left(r+(2)/(\pi r^2)\right)\\ \boxed{A=2\pi r^2+(4)/(r)}`