Question

B) Here are the first four terms of another sequence.

7
11 15 19
Write an expression for the nth term of this sequence.

Answer 1

`a_(n)` = 4n + 3

Explanation:

There is a common difference between consecutive terms, that is

11 - 7 = 15 - 11 = 19 - 15 = 4

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 = 7 and d = 4 , then

`a_(n)` = 7 + 4(n - 1) = 7 + 4n - 4 = 4n + 3