Bài 3:
b: \(B_1=-\left|2x-3\right|+2\le2\forall x\)
Dấu '=' xảy ra khi \(x=\dfrac{3}{2}\)
\(B_2=-\left|x+4\right|+5\le5\forall x\)
Dấu '=' xảy ra khi x=-4
Bài 3:
b) Xét số \(-B_3=6+\left|x+4\right|\ge6\Rightarrow B_3\le-6\)
Dấu '=' xảy ra \(\Leftrightarrow x=-4\)
\(3,\\ b,B_1=2-\left|3-2x\right|\le2\)
Dấu \("="\Leftrightarrow x=\dfrac{3}{2}\)
\(B_2=5-\left|x+4\right|\le5\)
Dấu \("="\Leftrightarrow x=-4\)
\(B_3=-6-\left|x+4\right|\le-6\)
Dấu \("="\Leftrightarrow x=-4\)
\(c,15-\left(x^2-4\right)^2-\left|x+2\right|\le15\)
Dấu \("="\Leftrightarrow\left\{{}\begin{matrix}x^2-4=0\\x+2=0\end{matrix}\right.\Leftrightarrow x=-2\)
\(C_2=10-\left|2x-1\right|-\left|y+x\right|\le10\)
Dấu \("="\Leftrightarrow\left\{{}\begin{matrix}x=\dfrac{1}{2}\\y=-x\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}x=\dfrac{1}{2}\\y=-\dfrac{1}{2}\end{matrix}\right.\)