Найдите значение выражения (Cos π/12+cos π/6)/ cos π/8•cosπ/24

Решите задачу:

$\frac{cos\frac{\pi}{12}+cos\frac{\pi}{6}}{cos\frac{\pi}{8}\cdot cos\frac{\pi}{24}} = \frac{2cos\frac{\frac{\pi}{12}+\frac{\pi}{6}}{2}\cdot cos \frac{\frac{\pi}{6}-\frac{\pi}{12}}{2} }{cos\frac{\pi}{8}\cdot cos\frac{\pi}{24}} = \frac{2cos\frac{3\pi}{24}\cdot cos\frac{\pi}{24}}{cos\frac{\pi}{8}\cdot cos\frac{\pi}{24}} = \frac{2cos\frac{\pi}{8}}{cos\frac{\pi}{8}} =2$