$\displaystyle \frac{x}{x+5}$

I have an answer in my solutions manual that I think might be a typo. It is my understanding right now that the second derivative of x is 0. So if that is correct then the second derivative of the equation at the top of my post should then be:

$\displaystyle \frac{0}{0}$

I want to make sure I have not made an error.

My answer:

$\displaystyle 0$

Thank in advance...