# Homework Help: Find derivative where f(x) has three products

1. Oct 14, 2012

### cloudboy

1. The problem statement, all variables and given/known data

Trying to find all Max and Min.

F(x) = x^(2/3)(x^2 - 4)

2. Relevant equations
I know to use the product rule

3. The attempt at a solution

I tried and got this answer:

x^(10/3) + (2(x+2)(x-2)) / 3x^(1/3)

2. Oct 14, 2012

### dcassell

You could also just multiple the x^2/3 through so that you don't have to bother with the product rule.

3. Oct 14, 2012

### cloudboy

Thanks a lot! I got (8(x+1)(x-1)) / (3x^(1/3)) which is the right answer.

4. Oct 14, 2012

$\frac{2}{3}$x$^{-1/3}$*(x$^{2}$-4) + 2*x$^{5/3}$
x$^{-1/3}$*($\frac{8}{3}$x$^{2}$ - $\frac{8}{3}$)