## Algebra and Trigonometry 10th Edition

Domain: $x \ne \pm 3$ Vertical asymptotes: $x=3$ Horizontal asymptotes: $y=0$
Domain: $x^2 -9 \ne 0$ $x^2 \ne 9$ $x \ne \pm3$ Identify vertical asymptotes: $\frac{x+3}{x^2 -9}=\frac{x+3}{(x-3)(x+3)}= \frac {1}{x-3}$ $x=3$ Identify any horizontal asymptotes: $f(x) \rightarrow 0$ as $x\rightarrow \infty$ $y=0$