$\frac{-2}{x+1}$ -$\frac{x}{x-1}$ =2
⇒ $\frac{-2(x-1)}{(x+1)(x-1)}$ -$\frac{x(x-1)}{(x-1)(x+1)}$ =2
⇔ $\frac{-2(x-1)-x(x-1)}{(x-1)(x+1)}$ =2
⇔ $\frac{-2x+1-x^{2}-x}{x^{2}-1}$=2
⇔ -2x+1-x²-x=2(x²-1)
⇔ -3x+1-x²=2x²-2
⇔ 3x²+3x-3=0
⇔ 3x(x+1)-3=0
⇔ \(\left[ \begin{array}{l}3x-3=0\\(x+1)-3=0\end{array} \right.\)
⇔ \(\left[ \begin{array}{l}3x=3\\x+1=3\end{array} \right.\)
⇔\(\left[ \begin{array}{l}x=1\\x=2\end{array} \right.\)
