Question

Tìm x, y, z biết : |x - y - 1| + |x + 2| lớn hơn hoặc bằng 0.

 

Answer 1

\(\left|x-y-1\right|+\left|x+2\right|\ge0\)

Do \(\left|x-y-1\right|,\left|x+2\right|\ge0\forall x,y\)

\(\Rightarrow\left\{{}\begin{matrix}x-y-1=0\\x+2=0\end{matrix}\right.\)\(\Rightarrow\left\{{}\begin{matrix}x=-2\\y=-3\end{matrix}\right.\)