Đáp án:
`|x - 2| -1 = 0`
`⇔ |x - 2| = 0 + 1 = 1`
`⇒` $\left[\begin{matrix} x - 2 = 1\\ x - 2 = -1\end{matrix}\right.$
`⇒` $\left[\begin{matrix} x = 1 + 2\\ x = -1 + 2\end{matrix}\right.$
`⇒` $\left[\begin{matrix} x = 3\\ x = 1\end{matrix}\right.$
Vậy `x = 3` hoặc `x = 1`
`-1/4 .13 9/11 - 0,25 . 6 2/11`
`= -1/4 . 13 9/11 - 1/4 . 6 2/11`
`= -1/4 (13 9/11 + 6 2/11)`
`= -1/4 . [(13 + 6) + (9/11 + 2/11)]`
`= -1/4. (19 + 1)`
`= -1/4 . 20`
`= - 5`
