|x-1| = 2x+3
Giả sử x- 1≥ 0
=> $\left \{ {{x - 1≥0} \atop {x-1 = 2x+3}} \right.$
=> $\left \{ {{x≥1} \atop {x+3 = -1}} \right.$
=> $\left \{ {{x≥1} \atop {x=-4}} \right.$ (Loại)
Giả sử x-1≤0
=> $\left \{ {{x-1≤0} \atop {x-1=-2x-3}} \right.$
=> $\left \{ {{x≤1} \atop {-3x-3 = -1}} \right.$
=> $\left \{ {{x≤1} \atop {-3x = 2}} \right.$
=> $\left \{ {{x≤1} \atop {x= \frac{-2}{3} }} \right.$ (CHỌN)
Vậy x = $\frac{-2}{3}$
HOK TỐT!
