\(H=\dfrac{x-\sqrt{x}+2-x-\sqrt{x}}{\left(\sqrt{x}-2\right)\left(\sqrt{x}+1\right)}.\dfrac{\sqrt{x}-2}{\sqrt{x}-1}\\ H=\dfrac{-2\left(\sqrt{x}-1\right)}{\left(\sqrt{x}-2\right)\left(\sqrt{x}+1\right)}.\dfrac{\sqrt{x}-2}{\sqrt{x}-1}=\dfrac{-2}{\left(\sqrt{x}+1\right)}\)
=(\(\dfrac{x-\sqrt{x}+2}{x-\sqrt{x}-2}\)-\(\dfrac{x}{x-2\sqrt{x}}\)) : \(\dfrac{1-\sqrt{x}}{2-\sqrt{x}}\) (x>0,x≠2)
=(\(\dfrac{x-\sqrt{x}+2}{(\sqrt{x}-2)(\sqrt{x}+1)}\)-\(\dfrac{x}{\sqrt{x}(\sqrt{x}-2)}\)) : \(\dfrac{1-\sqrt{x}}{2-\sqrt{x}}\)
=\(\dfrac{x\sqrt{x}-x+2\sqrt{x}-x\sqrt{x}+x}{\sqrt{x}(\sqrt{x}-2)(\sqrt{x}+1)}\) : \(\dfrac{1-\sqrt{x}}{2-\sqrt{x}}\)
=\(\dfrac{2\sqrt{x}}{\sqrt{x}(\sqrt{x}-2)(\sqrt{x}+1)}\) . \(\dfrac{2-\sqrt{x}}{1-\sqrt{x}}\)
=\(\dfrac{2}{(\sqrt{x}-2)(\sqrt{x}+1)}\) . \(\dfrac{\sqrt{x}-2}{\sqrt{x}-1}\)
=\(\dfrac{2}{x-1}\)
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