$$y = \sqrt { \frac { x ^ { 2 } - 2 x + 5 } { x + 2 } } - \frac { x } { \sqrt { x ^ { 3 } - 9 x } }$$
$y=\left(x\left(x^{2}-9\right)\right)^{-\frac{1}{2}}\left(\sqrt{\frac{x^{2}-2x+5}{x+2}}\sqrt{x\left(x^{2}-9\right)}-x\right)$
$x\neq -2\text{ and }x\neq -3\text{ and }x\neq 3\text{ and }x\neq 0$
$y=\frac{\sqrt{x\left(x^{2}-9\right)\left(x^{2}-2x+5\right)}-\sqrt{x+2}x}{\sqrt{x\left(x+2\right)\left(x^{2}-9\right)}}$
$x>3\text{ or }\left(x>-2\text{ and }x<0\right)$
