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[imath]\dfrac{2+\sqrt3}{2+\sqrt{2+\sqrt3}}+\dfrac{2-\sqrt3}{2-\sqrt{2+\sqrt3}}[/imath]
[imath]=\dfrac{(2+\sqrt3)(2-\sqrt{2+\sqrt3})}{(2+\sqrt{2+\sqrt3})(2-\sqrt{2+\sqrt3})}+\dfrac{(2-\sqrt3)(2+\sqrt{2+\sqrt3})}{(2+\sqrt{2+\sqrt3})(2-\sqrt{2+\sqrt3})}[/imath]
[imath]=\dfrac{4+2\sqrt3-(2+\sqrt3)\sqrt{2+\sqrt3}+4-2\sqrt3+(2-\sqrt3)\sqrt{2+\sqrt3}}{4-(2+\sqrt3)}[/imath]
[imath]=\dfrac{8-2\sqrt3\sqrt{2+\sqrt3}}{2-\sqrt3}=\dfrac{8-\sqrt6\sqrt{4+2\sqrt3}}{2-\sqrt3}=\dfrac{8-\sqrt6(\sqrt3+1)}{2-\sqrt3}=\dfrac{8-3\sqrt2-\sqrt6}{2-\sqrt3}[/imath]
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