1. ## Proving second derivative

Hi,

I hope someone can help me with the following question:

I got a different expression for the second derivative than the one above. I'm wondering whether I'm solving this incorrectly or the textbook solution is just wrong. The textbook solution is as follows:

Let me know.

- olivia

2. ## Re: Proving second derivative

Originally Posted by otownsend
Hi,

I hope someone can help me with the following question:

I got a different expression for the second derivative than the one above. I'm wondering whether I'm solving this incorrectly or the textbook solution is just wrong. The textbook solution is as follows:

Let me know.

- olivia
The textbook is correct

3. ## Re: Proving second derivative

You say you "got a different expression for the second derivative" but don't say what you got. If you would show what you did and what expression you got, we could point out your error. That will help you more than just pointing out that you are wrong.

4. ## Re: Proving second derivative

Yeah sorry, I understand now where I went wrong. Don't need help anymore