Question

B= |2x+1|  |2y-1| +2

típ nha

Answer 1

`B= |2x+1| + |2y-1| +2`

Do \(\left\{{}\begin{matrix}\left|2x+1\right|\ge0\\\left|2y-1\right|\ge0\end{matrix}\right.\) `∀x => |2x + 1| + |2y-1| >= 0 ∀x`

`=>  |2x + 1| + |2y-1| +2 >= 2 ∀x`

Hay `B >=2 `

Dấu = có khi: 

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

Vậy `B_(min) = 2` khi `x = -1/2; y = 1/2`

Answer 2

dấu ở giữa là gì vậy bn