# Math Help - [SOLVED] Average minimum cost?

1. ## [SOLVED] Average minimum cost?

Cost function: C(x)=4x^2 + 100

Minimum average cost=?

2. Originally Posted by bgwarhawk
Cost function: C(x)=4x^2 + 100

Minimum average cost=?
The first derivative is 8x, did you figure that out?

At what x value does that equal 0?

You can then solve for $8x=0$

$\therefore 4 x^2 + 100$ is at a minimum at $x = 0$,
and the value of the function at $x = 0$ is $100$

3. see i understand the minimizing the average cost what my problem is the maximizing the average cost

oh and what the heck do you do when you do not have both the revenue and cost problems how do you take the derivative to figure it out if you only have one problem with two variables and one constant?...