$\frac{x+1}{x-2}$ -$\frac{5}{x+2}$ =$\frac{12}{x² -4}$ ĐKXĐ:x$\neq$ ±2
(=)$\frac{x+1}{x-2}$ -$\frac{5}{x+2}$-$\frac{12}{x² -4}$=0
(=)$\frac{x+1}{x-2}$ -$\frac{5}{x+2}$ -$\frac{12}{(x-2)(x+2)}$=0
(=)$\frac{(x+1)(x+2)-5(x-2)-12}{(x-2)(x+2)}$ =0
(=)x²+2x+x+2-5x+10-12=0
(=)x²-2x=0
(=)x(x-2)=0
(=)\(\left[ \begin{array}{l}x=0\\x-2=0\end{array} \right.\) (=)\(\left[ \begin{array}{l}x=0\\x=2 (Loại)\end{array} \right.\)
S={0}
