#### Answer

(a) $\mathcal{x}$ $\gt$ 2
(b) -3 $\leq$ $\mathcal{x}$ $\leq$ -1
(c) 0 $\leq$ $\mathcal{x}$ $\lt$ 9

#### Work Step by Step

In (a) $\mathcal{x}$ $\gt$ 2 because the other end of the limit is $\infty$
In (b) and (c) numbers are given and (parentheses) are closed intervals and [brackets] are open inverals.