=>||3x-3|+2x+1|=3x+1
=>|3x-3|+2x+1=3x+1 hoặc |3x-3|+2x+1=-3x-1
=>|3x-3|=x hoặc |3x-3|=-5x-2
Trường hợp 1: |3x-3|=x
\(\Leftrightarrow\left\{{}\begin{matrix}x>=0\\\left(3x-3-x\right)\left(3x-3+x\right)=0\end{matrix}\right.\Leftrightarrow x\in\left\{\dfrac{3}{2};\dfrac{3}{4}\right\}\)
Trường hợp 2: |3x-3|=-5x-2
\(\Leftrightarrow\left\{{}\begin{matrix}x< =-\dfrac{2}{5}\\\left(3x-3+5x+2\right)\left(3x-3-5x-2\right)=0\end{matrix}\right.\)
\(\Leftrightarrow\left\{{}\begin{matrix}x< =-\dfrac{2}{5}\\\left(8x-1\right)\left(-2x-5\right)=0\end{matrix}\right.\Leftrightarrow x=-\dfrac{5}{2}\)