Write a recursive formula for the arithmetic sequence.
$\(\left\)\(\lbrace\)8,2,-4,-10,\(\ldots\[\right\]\rbrace\)$

Find the general formula for the arithmetic sequence below. Without using a recursive formula, calculate the $30^{\(\th\)}$ term.

$\(\left\)\(\lbrace\)-9,-4,1,6,\(\ldots\[\right\]\rbrace\)$