# Need help Determining the Derivative

1. Sep 24, 2011

f(x)= -3x^4/(4x-8)^(1/2),

f'(x)=?

Cannot figure out how to do this one, would appreciate help finding my mistakes!

I'm sure you all cna find the answer yourself but for convenience it is -3x^3(7x-16)/(4(x-2)^(3/2))

#### Attached Files:

• ###### IMG00934-20110924-1151.jpg
File size:
14 KB
Views:
58
Last edited: Sep 24, 2011
2. Sep 24, 2011

### gb7nash

At the step:

$$\frac{(4x-8)(-12x^3) +6x^4}{(4x-8)^{\frac{1}{2}}(4x-8)}$$

We can factor a number out of (4x-8)1/2. We can also factor a number out of (4x-8). Once you get to the last step of your work, you can factor out a number from (14x-32).

3. Sep 24, 2011