5 \\ x < 5" alt="y = 3x {}^{2} + x - 11 \\ d(y) = - \infty < x < \infty \\2)y = \sqrt{x - 3} \\ x - 3 \geqslant 0 \\d(y) = x \geqslant 3 \\ 3) \sqrt{x {}^{2} - 9} \\ x {}^{2} - 9 \geqslant 0 \\ x {}^{2} \geqslant 9 \\ d(y) = x \geqslant 3 \\ x \leqslant - 3 \\ 4) \frac{3 - x}{x - 5} \\ d(y) = x > 5 \\ x < 5" align="absmiddle" class="latex-formula">