[tex]Zal:\\\\x-1 \neq 0 \ \ i \ \ x^{2}-1 \neq 0\\\\x \neq 1 \ \ i \ \ (x+1)(x-1) \neq 0\\\\x \neq 1 \ \ i \ \ x \neq -1\\\\D = R \setminus \{-1,1\}[/tex]
[tex]\frac{-x^{2}+3x}{x-1}:\frac{2x-6}{x^{2}-1} = \frac{-x(x-3)}{x-1}:\frac{2(x+3)}{(x-1)(x+1)} = \frac{-x(x-3)}{x-1}\cdot\frac{(x-1)(x+1)}{2(x-3)} =\frac{-x(x+1)}{2}=\\\\=-\frac{x^{2}+1}{2}[/tex]
