Сократите mn-3n+3-m/m^2-9

[latex] \frac{mn-3n+3-m}{m^{2}-9 } = \frac{mn-m+3-3n}{m^{2}-9 } = \frac{m(n-1)-3(n-1)}{(m-3)(m+3)}= \frac{n-1}{m+3} [/latex]