# Math Help - use l'hospitals rule

1. ## use l'hospitals rule

i dont even know where to begin with this?

2. ## Re: use l'hospitals rule

Originally Posted by pnfuller
i dont even know where to begin with this?
Originally Posted by pnfuller
i dont even know where to begin with this?
Actually that can't be done unless it says that $f$ is differentiable.
If we assume that is what the question means then
what if $\frac{d[-f(x-h)]}{dh}=~?$.

3. ## Re: use l'hospitals rule

Since the problem says that f' (NOT f) is continuous, I think we can assume that f is differentiable!

pnfuller, since the problem says "use L'Hopitals rule", perhaps you could begin by doing that?

4. ## Re: use l'hospitals rule

Originally Posted by HallsofIvy
Since the problem says that f' (NOT f) is continuous, I think we can assume that f is differentiable!
It does not show $f'$ on this computer.
It could be that the image is so dark.
I wish we could ban posting questions as images.

5. ## Re: use l'hospitals rule

well how do you take the derivative of the numerator with all the different variables?
Originally Posted by HallsofIvy
Since the problem says that f' (NOT f) is continuous, I think we can assume that f is differentiable!

pnfuller, since the problem says "use L'Hopitals rule", perhaps you could begin by doing that?