Lần này chắc là đúng, hổng lẽ sai nữa thì cmnr:-SS
\[\begin{array}{l}
\sqrt {\frac{{2\sqrt x + 1}}{{x + \sqrt x }}} = \sqrt {2\sqrt x + 1} - \sqrt {x + \sqrt x } + 1\\
\Leftrightarrow \frac{{\sqrt {2\sqrt x + 1} - \sqrt {x + \sqrt x } }}{{\sqrt {x + \sqrt x } }} = \sqrt {2\sqrt x + 1} - \sqrt {x + \sqrt x } \\
\Leftrightarrow \left( {\sqrt {2\sqrt x + 1} - \sqrt {x + \sqrt x } } \right)\left( {\frac{1}{{\sqrt {x + \sqrt x } }} - 1} \right) = 0\\
\Leftrightarrow \left( {\frac{{\sqrt x + 1 - x}}{{\sqrt {2\sqrt x + 1} + \sqrt {x + \sqrt x } }}} \right)\left( {\frac{{1 - \sqrt {x + \sqrt x } }}{{\sqrt {x + \sqrt x } }}} \right) = 0\\
\Leftrightarrow - \left( {\frac{{\sqrt x - (x - 1)}}{{\sqrt {2\sqrt x + 1} + \sqrt {x + \sqrt x } }}} \right)\left( {\frac{{\sqrt x + (x - 1)}}{{\left( {1 + \sqrt {x + \sqrt x } } \right)\sqrt {x + \sqrt x } }}} \right) = 0\\
\Leftrightarrow x - {(x - 1)^2} = 0\\
\Leftrightarrow - {x^2} + 3x - 1 = 0\\
\Leftrightarrow x = \frac{{3 \pm \sqrt 5 }}{2}
\end{array}\]