# Homework Help: Summation Notation - Variable in the exponent

1. Mar 1, 2008

### Goldenwind

[SOLVED] Summation Notation - Variable in the exponent

1. The problem statement, all variables and given/known data

This is an example formula.

How do I solve a summation if something is in the form of Sum(c^i), where c is some constant?

2. Mar 2, 2008

### Dick

Then it's geometric series. You'll want |c|<1.

3. Mar 2, 2008

Thank-you :)