\(\Leftrightarrow\frac{x+x-m}{x-m}+\frac{x+2-3}{x+2}=3\)\(\left(ĐKXĐ:x\ne-2,m\right)\)
\(\Leftrightarrow\frac{x}{x-m}+1-\frac{3}{x+2}+1=3\)
\(\Leftrightarrow\frac{x\left(x+2\right)-3\left(x-m\right)}{\left(x-m\right)\left(x+2\right)}=1\)
\(\Leftrightarrow x^2+2x-3x+3m=x^2-mx+2x-2m\)
\(\Leftrightarrow mx-3x+5m=0\)
\(\Leftrightarrow x=-\frac{5m}{m-3}\)(1)
Để (1) là nghiệm thì \(\frac{5m}{3-m}\ne\left(m,-2\right)\)
Giải ra thì m\(\ne-2\)
Để \(x\)<0 thì
\(\left[{}\begin{matrix}\left\{{}\begin{matrix}5m< 0\\3-m>0\end{matrix}\right.\\\left\{{}\begin{matrix}5m>0\\3-m< 0\end{matrix}\right.\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}0>m\\m>3\end{matrix}\right.\)
