CPM Homework Help : INT1 Problem 7-103

Examine each sequence below. State whether it is arithmetic, geometric, or neither. For the sequences that are arithmetic, write a formula for $t(n)$ . For the sequences that are geometric, determine the common ratio.

$1, 4, 7, 10, 13, …$

$0, 5, 12, 21, 32, …$
Answer (b):
The sequence is neither arithmetic nor geometric.

$2, 4, 8, 16, 32, …$
Answer (c):
The sequence is geometric.
$r = 2$

$5, 12, 19, 26, …$
Hint (d):
Do the terms in the sequence increase by adding a constant amount or multiplying by a constant?

$x, x + 1, x + 2, x + 3, …$
Hint (e):
See part (d).
Answer (e):
The sequence is arithmetic.
$d = 1$

$3, 12, 48, 192, …$
Hint (f):
See part (d).