# Math Help - Calc question, infinite sum

1. ## Calc question, infinite sum

If anyone could explain how this is done since there's a similar problem I have to do for homework, I would greatly appreciate it.

C' = 1 - (1/2) + (1/6) - (1/24) +-...+ (-1)^n * (1/n!) +...

Find the sum of series C'. (Hint: Use the Maclaurin series for e^x.)

2. Originally Posted by clockingly
If anyone could explain how this is done since there's a similar problem I have to do for homework, I would greatly appreciate it.

C' = 1 - (1/2) + (1/6) - (1/24) +-...+ (-1)^n * (1/n!) +...

Find the sum of series C'. (Hint: Use the Maclaurin series for e^x.)
What is the problem,

This is e^{-x} evaluated at x=-1.

Thus, it is 1/e.