Question

What is the recursive formula for the sequence?8, 6, 4, 2, 0, ...an = an-1 - 2, where a = 8an = an-1 + 2, where a = 8an = 2n-1 - 2, where a = -2an = 2n-1 + 2, where a = -2

Answer 1

Arithmetic sequences are given by the expression:

$\begin{gathered} a_n=a_1+d(n-1) \\ a_n=the\text{ term we need to find} \\ a_1=first\text{ term of the sequence} \\ d=\text{ common difference} \end{gathered}$

So, in this case the formula would be:

$a_n=8-2(n-1)$