1. Section 12-4 -Finding sums of geometric series -Using Sigma notation Taylor Morgan

2. Vocab. Geometric Sequence-(From previous section) sequence in which each term after the first is found by multiplying a ratio, known as the common ratio, r, to the previous term Series- an indicated sum of the terms in a sequence Geometric series- an indicated sum of the terms in a geometric sequence Ex. 1) 18, 9, 4.5 Ex.2) 4+8+16+32 Ex. 3) -9, 3,-1 Ex.4) 3/8+ 3/16 + 3/32 Geometric SequenceGeometric Series

3. Terms in a Series represents the sum of the first n terms in a series So, for example, is the sum of the first four terms Ex. For the series ½ +1+2+4, is ½ + 1 + 2 + 4 is 7.5

4. Where: r= the common ratio by dividing two consecutive terms n= number of terms a = 1 st term in a series a = nth term in a series 1 n Sum of an Geometric Series The sum of the first n terms of an arithmetic series is given by

5. Find the Sum of an Geometric Series Given the following formula: Find the sum of the first 5 times of the geometric Sequence: 100 + 20 + …