Bài 2:
a: \(A=\left(\dfrac{-x-1+2x-2-x+5}{\left(x-1\right)\left(x+1\right)}\right)\cdot\dfrac{\left(x-1\right)\left(x+1\right)}{1-2x}\)
\(=\dfrac{2}{1-2x}=\dfrac{-2}{2x-1}\)
b: Để A nguyên thì \(2x-1\in\left\{1;-1;2;-2\right\}\)
=>\(x\in\left\{0;\dfrac{3}{2};-\dfrac{1}{2}\right\}\)
c: Để |A|=A thì A>=0
=>-2/2x-1>=0
=>2x-1<0
=>x<1/2




