\(N=\dfrac{x}{\sqrt{x}-1}+\dfrac{\sqrt{x}-2x}{x-\sqrt{x}}(dkxd:x>0,x\ne1)\)
\(=\dfrac{x}{\sqrt{x}-1}+\dfrac{\sqrt{x}-2x}{\sqrt{x}\left(\sqrt{x}-1\right)}\)
\(=\dfrac{\sqrt{x}^2+\sqrt{x}\left(1-2\sqrt{x}\right)}{\sqrt{x}\left(\sqrt{x}-1\right)}\)
\(=\dfrac{\sqrt{x}\left(\sqrt{x}+1-2\sqrt{x}\right)}{\sqrt{x}\left(\sqrt{x}-1\right)}\)
\(=\dfrac{\sqrt{x}\left(-\sqrt{x}+1\right)}{\sqrt{x}\left(\sqrt{x}-1\right)}\)
\(=\dfrac{-\left(\sqrt{x}-1\right)}{\sqrt{x}-1}\)
\(=-1\)
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