Đáp án:
`x = 1/2; y = (-3)/2; z = 5/2`
Giải thích các bước giải:
`|x - 1/2| + |y + 3/2| +|z - 5/2| ≤ 0`
Do: $\begin{cases}\bigg|x- \dfrac{1}{2}\bigg| \ge 0 \forall x\\\bigg|y + \dfrac{3}{2}\bigg| \ge 0 \forall y \\ \bigg|z - \dfrac{5}{2}\bigg| \ge 0 \forall z\\\end{cases} \Rightarrow \bigg|x - \dfrac{1}{2}\bigg|+\bigg|y+\dfrac{3}{2}\bigg|+\bigg|z-\dfrac{5}{2}\bigg| \ge 0$
Dấu $"="$ xảy ra $⇔\begin{cases}\bigg|x-\dfrac{1}{2}\bigg|=0\\ \bigg|y + \dfrac{3}{2}\bigg|=0\\ \bigg|z - \dfrac{5}{2}\bigg|=0\\\end{cases} ⇔ \begin{cases}x-\dfrac{1}{2}=0\\y + \dfrac{3}{2}=0\\z - \dfrac{5}{2}=0\\\end{cases}⇔ \begin{cases} x=\dfrac{1}{2}\\y=\dfrac{-3}{2}\\z=\dfrac{5}{2}\\\end{cases}$
Vậy `x = 1/2; y = (-3)/2; z = 5/2`
