Question

Answer 1

a: \(A=\left(\dfrac{x^2}{x\left(x-2\right)\left(x+2\right)}-\dfrac{6}{3\left(x-2\right)}+\dfrac{1}{x+2}\right):\dfrac{x^2-4+10-x^2}{x+2}\)

\(=\left(\dfrac{x}{\left(x-2\right)\left(x+2\right)}-\dfrac{2}{x-2}+\dfrac{1}{x+2}\right):\dfrac{6}{x+2}\)

\(=\dfrac{x-2x-4+x-2}{\left(x-2\right)\left(x+2\right)}\cdot\dfrac{x+2}{6}\)

\(=\dfrac{-6}{6}\cdot\dfrac{1}{x-2}=\dfrac{-1}{x-2}\)

b: |x-2|=4

=>x-2=4 hoặc x-2=-4

=>x=6(nhận) hoặc x=-2(loại)

Thay x=6 vào A, ta được: 

\(A=\dfrac{-1}{6-2}=\dfrac{-1}{4}\)

c: Để A=2 thì x-2=-1/2

hay x=3/2