Answer:
[tex]4. x ^ { 2 } -5x+6 \div x-2 \\ \frac{\left(x^{2}-5x-2\right)x}{x}+\frac{6}{x} \\ \\ \frac{\left(x^{2}-5x-2\right)x+6}{x} \\ \\ \frac{x^{3}-5x^{2}-2x+6}{x} \\ \\ \frac{\left(x-1\right)\left(x-\left(2-\sqrt{10}\right)\right)\left(x-\left(\sqrt{10}+2\right)\right)}{x}[/tex]
