2 câu trả lời
Giải thích các bước giải:
`|x + 1| - |1/2x - 3| = 0`
`-> |x + 1| = |1/2x - 3|`
`TH1 :`
`-> x + 1 = 1/2x - 3`
`-> x - 1/2x = -3 - 1`
`-> 1/2x = -4`
`-> x = -8`
`TH2 :`
`-> x + 1 = -1/2x + 3`
`-> x + 1/2x = 3 - 1`
`-> 3/2x = 2`
`-> x = 4/3`
`Vậy x \in {-8 ; 4/3}`
` | x + 1 | - | 1/2 x - 3 | = 0`
`=>` `| x + 1 | = | 1/2 x - 3 |`
`=>` $\left[\begin{matrix} x + 1 = -( \dfrac{-1}{2} x - 3 )\\ x + 1 = \dfrac{1}{2}x-3\end{matrix}\right.$
`=>` $\left[\begin{matrix} x + 1 = \dfrac{-1}{2} x + 3 \\ x + 1 = \dfrac{1}{2} x -3\end{matrix}\right.$
`=>` $\left[\begin{matrix} \dfrac{3}{2} x = 3 - 1\\ \dfrac{-1}{2} x = -3 - 1\end{matrix}\right.$
`=>` $\left[\begin{matrix} \dfrac{3}{2} x = 2\\ \dfrac{1}{2} x = -4\end{matrix}\right.$
`=>` $\left[\begin{matrix} x = \dfrac{4}{3} \\ x = -8 \end{matrix}\right.$
${Vậy}$ `x in { 4/3 ; -8 }`
$\text{ #T_rex kẻ thống trị khu rừng }$
