Sửa đê: \(\left(\dfrac{3}{\sqrt{x}+1}+\dfrac{4-6\sqrt{x}}{x-1}+\dfrac{\sqrt{x}}{\sqrt{x}-1}\right)\cdot\left(\sqrt{x}+1\right)\)
\(=\dfrac{3\sqrt{x}-3+4-6\sqrt{x}+x+\sqrt{x}}{x-1}\cdot\left(\sqrt{x}+1\right)\)
\(=\dfrac{x-2\sqrt{x}+1}{\sqrt{x}-1}=\sqrt{x}-1\)