\(\Leftrightarrow\left(2x+1\right)\left(3x-2\right)-\left(5x-8\right)\left(2x+1\right)=0\)
\(\Leftrightarrow\left(2x+1\right)\left(3x-2-5x+8\right)=0\)
=>(2x+1)(6-2x)=0
=>x=-1/2 hoặc x=3
\(\left(2x+1\right)\left(3x-2\right)=\left(5x-8\right)\left(2x+1\right)\\ \Rightarrow\left(2x+1\right)\left(3x-2\right)-\left(5x-8\right)\left(2x+1\right)=0\\ \Rightarrow\left(2x+1\right)\left(3x-2-5x+8\right)=0\\ \Rightarrow\left(2x+1\right)\left(-2x+6\right)=0\\ \Rightarrow\left[{}\begin{matrix}x=-\dfrac{1}{2}\\x=3\end{matrix}\right.\)
Xét \(x=-\dfrac{1}{2}\) là một nghiệm của pt
Khi \(x\ne-\dfrac{1}{2}\) pt trở thành
\(3x-2=5x-8\)
\(\Leftrightarrow2x=6\)
\(\Leftrightarrow x=3\)
Vậy \(S=\left\{-\dfrac{1}{2};3\right\}\)
