Question

Complete the recursive formula of the geometric sequence 7, -14, 28, -56, ....

Answer 1

`a_(n)` = - 2
`a_(n-1)`

Explanation:

A geometric recursive formula has the form

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

where r is the common ratio

Here r = - 14 ÷ 7 = - 2, thus

`a_(n)` = - 2
`a_(n-1)` with a₁ = 7