Arithmetic Sequences

Arithmetic Sequence Notes

An __arithmetic_________ sequence is a set of __numbers/terms__ where the difference


between each pair of _consecutive_____ terms are the same. We call this difference the


common___difference______.



Find the common difference, d, for each arithmetic sequence.


  1. 2, 5, 8, 11, 14, …


5 - 2 = 3

8 - 5 = 3

11 - 8 = 3

14 - 11 = 3


common difference = 3


2. 7, 3, -1, -5, …


3 - 7 = -4

-1 - 3 = -4

-5 - -1= -4


common difference = -4


3. 4, 9, 14, 19, 24, …


9 - 4 = 5

14 - 9 = 5

19 - 14 = 5

24 - 19 = 5


common difference = 5





Terminology


d - difference



a1- first term



a2- second term



an- nth term



an-1- n -1 term