Question

An arithmetic sequence has this recursive formula:

What is the explicit formula for this sequence?

Answer 1

C

Explanation:

the explicit formula for an arithmetic sequence is

`a_(n)` = a₁ + (n - 1)d

where a₁ is the first term and d the common difference

from the recursive formula in the form

`a_(n)` =
`a_(n-1)` + d

given

`a_(n)` =
`a_(n-1)` - 7

with d = - 7 and a₁ = 4 , then explicit formula is

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