Question

For each sequence, determine whether it appears to be arithmetic, geometric, or neither.

1. 2, 4, 6, 8, ...
2. 9, 16, 25, 36, ...
3. 64, 32, 16, 8, ...

Answer 1

Explanation:

1. 2, 4, 6, 8, ...

This sequence has a common difference (+ 2). So it is arithmetic.

2. 9, 16, 25, 36, ...

This sequence has neither a common difference nor a common ratio.

3. 64, 32, 16, 8, ...

This sequence has a common ratio (× ½). So it is geometric.