Question

Write a recursive formula for the following arithmetic sequence.
8, 5, 2, −1,

Answer 1

`a_(n)` =
`a_(n-1)` - 3

Explanation:

A recursive formula allows a term in the sequence to be found from the previous term by adding the common difference to it.

Here d = 5 - 8 = - 3, thus

`a_(n)` =
`a_(n-1)` - 3 with a₁ = 8 ← recursive formula