# Identify the Sequence 1 , 2 , 3

, ,
This is an arithmetic sequence since there is a common difference between each term. In this case, adding to the previous term in the sequence gives the next term. In other words, .
Arithmetic Sequence:
This is the formula of an arithmetic sequence.
Substitute in the values of and .
Multiply by .
Combine the opposite terms in .
Subtract from .