Giải thích các bước giải:
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\begin{array}{l}
A = (\frac{{\sqrt x }}{{\sqrt x - 1}} - \frac{1}{{x - \sqrt x }}):(\frac{1}{{1 + x}} + \frac{2}{{x - 1}})\\
A = {\rm{[}}\frac{{\sqrt x }}{{\sqrt x - 1}} - \frac{1}{{\sqrt x .(\sqrt x - 1)}}{\rm{]: [}}\frac{{x - 1 + 2.(x + 1)}}{{(1 + x).(x - 1)}}{\rm{]}}\\
{\rm{A = }}\frac{{x - 1}}{{\sqrt x .(\sqrt x - 1)}}:\frac{{3x + 1}}{{(1 + x).(x - 1)}}\\
A = \frac{{(\sqrt x - 1).(\sqrt x + 1)}}{{\sqrt x .(\sqrt x - 1)}}.\frac{{(1 + x).(x - 1)}}{{3x + 1}}\\
A = \frac{{\sqrt x + 1}}{{\sqrt x }}.\frac{{(1 + x).(x - 1)}}{{3x + 1}}
\end{array}$
