\frac\sqrt3 + 1\sqrt3 - 1 \cdot \frac\sqrt3 + 1\sqrt3 + 1 = \frac(\sqrt3 + 1)^2(\sqrt3)^2 - (1)^2 = \frac3 + 2\sqrt3 + 13 - 1 = \frac4 + 2\sqrt32 = 2 + \sqrt3. - Portal da Acústica