Question

Consider the sequence: 7, 64, 121, 178, 235, ... where u, = 7

a.
State whether it is arithmetic or geometric. Show how you know.​

Answer 1

It is an arithmetic sequence.

Explanation:

64 - 7 = 57

121 - 64 = 57

178 - 121 = 57

We have a common difference of 57, so it is arithmetic.

The explicit formula for the nth term

= 7 +57(n - 1).