Sequences

This is also a pretty easy concept to pick up on.

A sequence is a list of numbers which form a pattern. We are going to look at two types of sequences: Arithmetic and Geometric.
An Arithmetic Sequence is a sequence that is characterized by adding the same number each time.
The formula for arithmetic sequences is
tn=t1 + (n-1) x d
d is what is added or the difference.
tn is __ terms

A Geometric Sequence is a sequence that is characterized by mulitplying the same number each time.
The formula for geometric is
tn=t1 x r^(n-1)
r is whatever is being mulitplied
n is the term number
tn is __ terms


Ex 1: Find the tn formula for the following sequence:
2,5,8,11
It is arithmetic since 3 is added each time. So we plug it into the tn formula.
Tn=2+(n-1)3
Tn=3n-1

Ex 2: Find the tn formula for the following sequence:
2,6,18,54

It is geometric since everything is multiplied by 3.
Tn=2(3)^n-1


-Sameer