1. Finite Geometric Series

2. Vocabulary:
 Geometric Series: is an indicated sum of terms of a geometric sequence.
Example – add the first 5 terms in this sequence 1, 2, 4, 8, 16, …
nth partial sum:  is the sum Sn of the first n terms in a sequence
Sn = = 31

3. Example 1: Consider the sequence 31 + 32 + 33 + 34 + 35 Find
This is a finite geometric series
sn = g1 + g2 + g3 + g4 + g5
The sum of a finite geometric series with first term g1 and a constant ratio of r is given by:

4. Example 1, cont.:
First, add = _______ Now use the formula to find :

5. Example 2:
Find

6. Example 3:
You have 2 children, each of them have 2 kids, etc. How many generations until you have 1000 descendants?

7. Closure Find the sum of the first ten terms in the geometric series:
-3, 9, -27, 81, …
Find the sum for the following: