1. The problem statement, all variables and given/known data In other words, I'm trying to use the "historical" version of that part of the Fundamental Theorem of Calculus to obtain the "powerful" version. 2. Relevant equations Chain rule (I think). 3. The attempt at a solution I can't find how to do this in my book, and I have a strong feeling that this involves the chain rule, but I'm not too sure how to get my vague idea into writing, and any help in doing so would be greatly appreciated!