Download presentation

Presentation is loading. Please wait.

Published byNorma Campbell Modified over 7 years ago

2
Choi

3
Geometric Sequence A sequence like 3, 9, 27, 81,…, where the ratio between consecutive terms is a constant, is called a geometric sequence. In a geometric sequence, the first term t1, is denoted as a. Each term after the first is found by multiplying a constant, called the common ratio, r, to the preceding term. The list then becomes. {a, ar, ar 2, ar 3,...}

4
Geometric Sequences Formulas In general: {a, ar, ar 2, ar 3,...,ar n-1,...}

5
Example 1 – Finding Formula for the nth term In the geometric sequences: {5, 15, 45,...}, find a) b) c) n n a) 5 5 b) 10 c) n n

6
Example 2 – Finding Formula for the nth term Given the geometric sequence: {3, 6, 12, 24,...}. a) Find the term b) Which term is 384? n n a) 14 b) We know the n th term is 384 !! Drop the bases!!

7
Example 3 – Find the terms in the sequence In a geometric sequence, t 3 = 20 and t 6 = -540. Find the first 6 terms of the sequence. (2) (1) (1)(2) Substitute into (1) Therefore the first 6 terms of the sequences are:

8
Example 4 – Find the terms in the sequence In a geometric sequence, t 3 = 20 and t 6 = -540. Find the first 6 terms of the sequence. METHOD 2 t n=20r (n-3) t 1 = 20r (1-3) To find a, we use the same thinking process!! Therefore the first 6 terms of the sequences are:

9
Example 5 – Applications of Geometric sequence Determine the value of x such that Form a geometric sequence. Find the sequences and Therefore the sequences are: 5+4, 2(5)+5, 4(5)+5,... 9, 15, 25,...

10
Homework: Check the web site Course Pack: Applications of Sequences

Similar presentations

© 2022 SlidePlayer.com Inc.

All rights reserved.

To make this website work, we log user data and share it with processors. To use this website, you must agree to our Privacy Policy, including cookie policy.

Ads by Google