\(=\dfrac{\sqrt{x-2-2\sqrt{x-2}\cdot2+4}+\sqrt{x-2+2\sqrt{x-2}\cdot2+4}}{\dfrac{2}{x}-\dfrac{2}{x}+1}\)
\(=\left|\sqrt{x-2}-2\right|+\left|\sqrt{x-2}+2\right|\)
TH1: x>=6
=>\(A=\sqrt{x-2}-2+\sqrt{x-2}+2=2\sqrt{x-2}\)
TH1: 2<=x<6
\(A=2-\sqrt{x-2}+\sqrt{x-2}+2=4\)