1. The problem statement, all variables and given/known data Here's the problem: Mod note: the last line is extraneous, and unrelated to this problem. 2. Relevant equations Definition of e (1-1/n)^n, etc. 3. The attempt at a solution My question is this: a) When do you know to use e in a situation like this? Is it when you have exponents in such a situation? b) Is this the definition of e? Or utilizing it somehow? c) If there is any sites/information that you can give me on this procedure, I would be grateful. In my calc studies this must have been skipped over and now it is being applied as if it has been taught to me already.