Download 32-Arithmetic Sequences

Name____________________________________
CC Algebra Lesson 32-Arithmetic Sequences
Date___________________
Ms. Socci
Aim: How do we find the nth term of a sequences?
an = a1 + (n – 1)d
Examples:
Find a formula for the sequence
6, 10, 14, 18, 22, … ,
Find a formula for the sequence
3, 5, 7, 9, …
Find a formula for the sequence
1, 3, 5, 7, …

An arithmetic sequence is a sequence of numbers in which each term is found by
adding the common difference (d) to the preceding term.
Directions: Find the next three terms of the following arithmetic sequences and state the
difference.
1) 2, 4, 6, ___, ___, ___
d =__________
2) -5, -3, -1, ___, ___, ___
d =__________
6. What is the common difference of
the arithmetic sequence
?
1)
3) 3
2)
3) 4, 1, -2, ____, ___, ___
d = _________
1 1 3
4) 4 , 2 , 4 , ___, ___, ___
d = _________
5) -3,-4,-5, ___, ___, ___
d = _________
4) 9
an = a1 + (n – 1)d
FINDING THE NTH TERM OF AN ARITHMETIC SEQUENCE:
an = the nth term
d = the common difference
a1 = the 1
st
term
n = the term number
Directions: Find the indicated term of each arithmetic sequence
7) The 20th term with a1 = 3 and d =4
8) The 10th term with a1 = -2 and d = 3
9) The 20th term with a1 = 5 and d = -2
10) Find a100 if a1 = -4 and d = -5
11) Find the 30th term of the following sequence 18,15,12,9,…..
12) Find the 25th term of the sequence -7, -4, -1, 2, ...
13) Find the number of terms in the sequence: 7, 10, 13, ..., 55.
14) Write an equation for the nth term of each arithmetic sequence.
a) a1 = 15 and d = 5
b) a1 = 72 and d = -5
c) 63, 70, 77, 84, …
d) -10, 10, 30, 50, …
15. What is a formula for the nth term of sequence B shown?
1)
2)
3)
4)