Question

giải pt:

|-3x|=2x-1

Answer 1

x

Answer 2

\(\Leftrightarrow\left|3x\right|=2x-1\)

\(\Leftrightarrow\left\{{}\begin{matrix}x>=\dfrac{1}{2}\\\left(3x\right)^2=\left(2x-1\right)^2\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}x>=\dfrac{1}{2}\\\left(3x-2x+1\right)\left(3x+2x-1\right)=0\end{matrix}\right.\)

\(\Leftrightarrow\left\{{}\begin{matrix}x>=\dfrac{1}{2}\\\left(x+1\right)\left(5x-1\right)=0\end{matrix}\right.\Leftrightarrow x\in\varnothing\)