Question

Nth term of sequence 9 11 13 15 17

Answer 1

`a_(n)` = 2n + 7

Explanation:

There is a common difference between consecutive terms , that is

11 - 9 = 13 - 11 = 15 - 13 = 17 - 15 = 2

This indicates the sequence is arithmetic with nth term

`a_(n)` = a₁ + (n - 1)d

where a₁ is the first term and d the common difference

Here a₁ = 9 and d = 2 , then

`a_(n)` = 9 + 2(n - 1) = 9 + 2n - 2 = 2n + 7