\(A=\left(\frac{x}{\sqrt{x}-1}-\sqrt{x}\right):\left(\frac{\sqrt{x}+1}{\sqrt{x}}-\frac{1}{1-\sqrt{x}}+\frac{2-x}{x-\sqrt{x}}\right)\)
\(=\frac{x-x+\sqrt{x}}{\sqrt{x}-1}:\frac{x-1+\sqrt{x}+2-x}{\sqrt{x}\left(\sqrt{x}-1\right)}\)
\(=\frac{\sqrt{x}}{\sqrt{x}-1}.\frac{\sqrt{x}\left(\sqrt{x}-1\right)}{\sqrt{x}+1}=\frac{x}{\sqrt{x}+1}\)