- #1

Karol

- 1,380

- 22

## Homework Statement

## Homework Equations

Maxima/minima are where the first derivative is 0

## The Attempt at a Solution

Surface area of the whole metal for creating the can (the end pieces i take as squares):

$$A=2\pi h+8r^2,~~V=\pi r^2 h~~\rightarrow~h=\frac{V}{\pi r^2}$$

$$A=2\pi \frac{V}{\pi r^2}+8r^2,~~A'=2V(-2)r^{-3}+16r=16r-\frac{4V}{r^3}$$

$$A'=0~\rightarrow~4r^4=V$$

I can't get rid of the volume V