\(e,\dfrac{2}{x+1}-\dfrac{1}{x-2}=\dfrac{3x-11}{\left(x+1\right)\left(x-2\right)}\left(ĐKXĐ:x\ne-1;x\ne2\right)\)
\(\Leftrightarrow2\left(x-2\right)-\left(x+1\right)=3x-11\)
\(\Leftrightarrow2x-4-x-1=3x-11\)
\(\Leftrightarrow2x-x-3x=4+1-11\)
\(\Leftrightarrow-2x=-6\)
\(\Leftrightarrow x=3\left(nhận\right)\)
Vậy \(S=\left\{3\right\}\)



