Question

Consider the first three terms of the sequence below.

14000, 12600, 11340

Complete a recursively-defined function to describe this sequence.
f(1) = _____
f(n) = f(n - 1) · ___, for n ≥ 2
The next term in the sequence is ____.

Answer 1

f(1) = 14000

f(n) = f(n - 1) · 0.9 , for n ≥ 2

The next term in the sequence is 10206 .

Explanation:

First we try to find the type of sequence it is.

Is there a common difference?

12600 - 14000 = -1400

11340 - 12600 = -1260

There is no common difference, so it is not an arithmetic sequence.

12600/14000 = 0.9

11340/12600 = 0.9

There is a common ratio, so this is a geometric sequence.

Each term is 0.9 times the previous term.

The next term is:

11340 * 0.9 = 10206

Answer:

f(1) = 14000

f(n) = f(n - 1) · 0.9 , for n ≥ 2

The next term in the sequence is 10206 .