a: \(A=\left(\dfrac{x}{\left(x-2\right)\left(x+2\right)}-\dfrac{2}{x-2}+\dfrac{1}{x+2}\right):\dfrac{x^2-4+10-x^2}{x+2}\)
\(=\dfrac{x-2x-4+x-2}{\left(x-2\right)\left(x+2\right)}\cdot\dfrac{x+2}{6}\)
\(=\dfrac{-6}{x-2}\cdot\dfrac{1}{6}=\dfrac{-1}{x-2}\)
b: |x-2|=4
=>x-2=4 hoặc x-2=-4
=>x=-2(loại) hoặc x=6(nhận)
Khi x=6 thì \(A=\dfrac{-1}{6-2}=\dfrac{-1}{4}\)
c: Để A=2 thì x-2=-1/2
hay x=3/2


