Question

Identify the correct formula for the following sequence. 2, -4, -10, -16, -22, ...

A. an = 6n - 8
B. an = -8n + 6
C. an = 8n - 6
D. an = -6n + 8

Answer 1

l What are the 1st 4 terms of the sequence defined by the following equation AN equals 5 × 2 in -1

Answer 2

D

Explanation:

The terms in the sequence have a common difference d between consecutive terms, that is

d = - 4 - 2 = - 10 - ( - 4) = - 16 - (- 10) = - 22 - (- 16) = - 6

This indicates the sequence is arithmetic with n th term

`a_(n)` = a₁ + (n - 1)d

where a₁ is the first term and d the common difference

Here a₁ = 2 and d = - 6, thus

`a_(n)` = 2 - 6(n - 1) = 2 - 6n + 6 = - 6n + 8 → D