TH1: \(x\ge\frac{-1}{3}\)
\(\Rightarrow3x+1-x-2=2x-1\)
TH2: \(x< \frac{-1}{3}\)
\(\Rightarrow-3x-1-x-2=-4x-3\)
Nhớ tick
\(A=\left|3x+1\right|-x-2\)
Với \(x\ge\frac{1}{3}\)
\(\Rightarrow3x+1-x-2\)
\(=\left(3x-x\right)+\left(1-2\right)\)
\(=2x-1.\)
Với \(x< -\frac{1}{3}\)
\(\Rightarrow-3x-1-x-2\)
\(=\left(-3x-x\right)+\left(-1-2\right)\)
\(=-4x-3.\)
Chúc bạn học tốt!