Bài 2:
a) \(A=\left|x+1001\right|+1\ge1\)
\(minA=1\Leftrightarrow x=-1001\)
b) \(B=\left|x-5\right|+10\ge10\)
\(minB=10\Leftrightarrow x=5\)
c) \(C=2\left|3x-1\right|-4\ge-4\)
\(minC=-4\Leftrightarrow x=\dfrac{1}{3}\)
Bài 3:
a) \(A=5-\left|5x+3\right|\le5\)
\(maxA=5\Leftrightarrow x=-\dfrac{3}{5}\)
b) \(B=-2-\left|1,4-x\right|\le-2\)
\(maxB=-2\Leftrightarrow x=1,4\)
c) \(N=\dfrac{1}{\left|x-2\right|+3}\le\dfrac{1}{0+3}=\dfrac{1}{3}\)
\(maxN=\dfrac{1}{3}\Leftrightarrow x=2\)
Bài 2:
a: \(A\ge1\forall x\)
Dấu '=' xảy ra khi x=-1001
b: \(B\ge10\forall x\)
Dấu '=' xảy ra khi x=5
