a represents the first term and is sometimes written as a 1.Įxample: if the first term of the sequence is 1 and the common ratio is 3, then each successive term can be obtained by multiplying the previous term by 3, and the sequence will look like this:įinding any term ( a n) in a geometric sequence:.The standard form of geometric sequences can be expressed as: The common ratio cannot equal 0 ( r ≠ 0 ).
The factor by which each successive term is multiplied is called the common ratio because it is common to all of the terms in the set.
A geometric sequence, also called a geometric series or geometric progression, is a set of numbers formed by multiplying each previous number in the set by a constant.