# Math Help - differentiation help

1. ## differentiation help

 Let for . What is ? id the answer just 5/7?

2. ## Re: differentiation help

Originally Posted by Tweety
 Let for . What is ? id the answer just 5/7?
No.

$y=\frac{5}{7x}=\frac{5}{7}x^{-1}$

Now you can just use the power rule

$\frac{d}{dx}x^{\alpha} = \alpha x^{\alpha -1}$

In your case $\alpha =-1$