Question

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

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