Вычислите sin 7π/12+sin π/12+cos π/12-cos 7π/12.

\[= 2 \cdot \frac{\sqrt{3}}{2} \cdot \frac{\sqrt{2}}{2} - 2 \cdot \frac{\sqrt{3}}{2} \cdot \left( - \frac{\sqrt{2}}{2} \right) =\]

\[= \frac{\sqrt{6}}{2} + \frac{\sqrt{6}}{2} = \frac{2\sqrt{6}}{2} = \sqrt{6}\]