Решение:
- 1. а)\[ \arccos(-1) - \arccos\frac{\sqrt{3}}{2} + \arccos\left(-\frac{\sqrt{2}}{2}\right) = \pi - \frac{\pi}{6} + \frac{3\pi}{4} = \frac{12\pi - 2\pi + 9\pi}{12} = \frac{19\pi}{12} \]
- 1. б)\[ \arccos\left(\operatorname{tg}\frac{\pi}{4}\right) = \arccos(1) = 0 \]
- 1. в)\[ \sin(\arccos 0) = \sin\left(\frac{\pi}{2}\right) = 1 \]
Ответ: а) 19π/12, б) 0, в) 1