A = (\frac{1}{1+\sqrt{x}}+\frac{1}{1-\sqrt{x}})[tex]\div[/tex] (\frac{1}{1-\sqrt{x}}-\frac{1}{1+\sqrt{x}})+\frac{1} {2\sqrt{x}}[/tex](đề)
=[tex] \frac{2}{1-x}:\frac{2\sqrt{x}}{1-x}+\frac{1}{2\sqrt{x}}[/tex]
=[tex]\frac{2}{2\sqrt{x}}+\frac{1}{2\sqrt{x}}[/tex]
=[tex]\frac{3}{2\sqrt{x}}[/tex]