#### Answer

(a) $[-3, 3]$
(b) $(-\infty,\ -3]\ \cup\ [3,\ \infty)$

#### Work Step by Step

(a) The solution of the inequality $|x|\leq 3$ is the interval ___$[-3, 3]$___.
(b) The solution of the inequality $|x|\geq 3$ is a union of two intervals ___$(-\infty,\ -3]\ \cup\ [3,\ \infty)$___