Question

What are the explicit equation and domain for an arithmetic sequence with a first term of 6 and a second term of 2?

an = 6 − 2(n − 1); all integers where n ≥ 1
an = 6 − 2(n − 1); all integers where n ≥ 0
an = 6 − 4(n − 1); all integers where n ≥ 0
an = 6 − 4(n − 1); all integers where n ≥ 1

Answer 1

We are given an arithmetic sequence with
First term, a₁ = 6
Second term, a₂ = 2
Therefore the common difference is d = -4.

The n-th term is

`a_(n) = a_(1) + (n-1)d \\ a_(n) = 6 - 4(n-1), \, for \, n \ge 1`

Answer:

`a_(n) = 6 - 4(n-1);` all integers where n ≥ 1