[tex]a=\frac{4}{\sqrt6+\sqrt2}+\sqrt2(\sqrt2-\sqrt3)+\frac{2}{\sqrt2}\\
a=\frac{4(\sqrt6-\sqrt2)}{(\sqrt6+\sqrt2)(\sqrt6-\sqrt2)}+2-\sqrt6+\frac{2\sqrt2}{2}\\
a=\frac{4(\sqrt6-\sqrt2)}{6-2}+2-\sqrt6+\sqrt2\\
a=\sqrt6-\sqrt2+2-\sqrt6+\sqrt2\\
a=2[/tex]