\[f(x) = \sqrt{x + 5} + \frac{6}{x^{2} - 4}\]
\[\left\{ \begin{matrix}
x + 5 \geq 0\ \\
x² - 4
eq 0 \\
\end{matrix} \right.\ \ \Longrightarrow \left\{ \begin{matrix}
x \geq - 5 \\
x²
eq 4\ \ \\
\end{matrix} \right.\ \Longrightarrow \left\{ \begin{matrix}
x \geq - 5 \\
x
eq \pm 2 \\
\end{matrix} \right.\ \]
\[D(f) = \lbrack - 5;\ - 2) \cup ( - 2;2) \cup (2;\ + \infty).\]