
A sequence is a set of numbers,
called terms, arranged in some
particular order.
Sequences

An arithmetic sequence is one in which
the same number is added or subtracted
from each element to get the next
element in the sequence.

The difference is called the common
difference.
Arithmetic Sequence

In a geometric sequence, each term is
equal to the previous term, multiplied (or
divided by) a constant.

This ratio is called the common ratio.

To find the common ratio, divide the
second term by the first term.
Geometric Sequence
Arithmetic formula:
 tn = t1 + (n - 1)d

◦ tn is the nth term, t1 is the first term, and d
is the common difference.
Geometric formula:
 tn = t1 . r(n - 1)

◦ tn is the nth term, t1 is the first term, and r
is the common ratio.
Formulas for Sequences