\[y = \frac{x^{2} - 3x - 4}{\sqrt{x^{2} + 2x + 1}} =\]
\[= \frac{(x - 4)(x + 1)}{\sqrt{(x + 1)^{2}}} =\]
\[= \frac{(x - 4)(x + 1)}{|x + 1|};\ \ \ x \neq - 1\]
\[x^{2} - 3x - 4 = 0\]
\[D = ( - 3)^{2} - 4 \cdot 1 \cdot ( - 4) =\]
\[= 9 + 16 = 25;\ \ \ \ \sqrt{D} = 5.\]
\[x_{1} = \frac{3 + 5}{2} = \frac{8}{2} = 4;\ \ \ \]
\[\ x_{2} = \frac{3 - 5}{2} = - \frac{2}{2} = - 1.\]