[tex]\displaystyle\bf y = \sqrt{x + 4} + \frac{5 - x}{ {x}^{2} - 1 } \\ \left \{ {{x + 4 \geqslant 0} \atop { {x}^{2} - 1\neq0 }} \right. \\ \displaystyle\bf\\\left \{ {{x \geqslant - 4} \atop {(x - 1)(x + 1)\neq0 }} \right. \\ \displaystyle\bf\\\left \{ {{x \geqslant - 4} \atop {x\neq1 \: \: \: and \: \: \: x\neq - 1 }} \right. \\ \\ x \: \epsilon \: [ - 4; \: - 1)U( - 1; \: 1)U(1; \: + \propto)[/tex]