\[\sqrt{\left( x^{2} - 11x + 24 \right)^{- 1}}\]
\[\frac{1}{x^{2} - 11x + 24}\]
\[x^{2} - 11x + 24 > 0\]
\[x_{1} + x_{2} = 11;\ \ x_{1} \cdot x_{2} = 24\]
\[x_{1} = 3;\ \ x_{2} = 8;\]
\[(x - 3)(x - 8) > 0\]
\[x < 3;\ \ x > 8.\]