[tex]A=\frac{\sqrt{2}+\sqrt{3}+\sqrt{6}+\sqrt{8}+4}{\sqrt{2}+\sqrt{3}+\sqrt{4}}[/tex]
Tử số[tex]=\left ( \sqrt{2}+\sqrt{3}+\sqrt{4} \right )+\sqrt{2}\left ( \sqrt{2} +\sqrt{3}+\sqrt{4}\right )=(\sqrt{2}+\sqrt{3}+\sqrt{4})(1+\sqrt{2})[/tex]
[tex]\Rightarrow A=1+\sqrt{2}[/tex]