a) \(\left|1-3x\right|-x-2=0\)
\(\Rightarrow\left|1-3x\right|=x+2\)
Có: \(\left|1-3x\right|=\left\{{}\begin{matrix}1-3x\forall x\le\dfrac{1}{3}\\3x-1\forall x>\dfrac{1}{3}\end{matrix}\right.\)
Xét: \(x\le\dfrac{1}{3}.\) Khi đó: 1 - 3x = x+2
\(\Rightarrow x=-\dfrac{1}{4}\)
Xét: \(x>\dfrac{1}{3}\) Khi đó: 3x - 1 = x + 2
\(\Rightarrow x=\dfrac{3}{2}\)
vậy \(x=-\dfrac{1}{4}orx=\dfrac{3}{2}\)