\[\boxed{\mathbf{600}\mathbf{.}}\]
\[\arcsin a = x,\ если\sin x = a\ \ и\ \]
\[- \frac{\pi}{2} \leq x \leq \frac{\pi}{2}.\]
\[Следовательно:\]
\[\arcsin\left( \sin x \right) = \arcsin a = x.\]
\[1)\ 7\arcsin\left( \sin\frac{\pi}{7} \right) = 7 \bullet \frac{\pi}{7} = \pi\]
\[2)\ 4\arcsin\left( \sin\frac{1}{2} \right) = 4 \bullet \frac{1}{2} = 2\]
\[3)\arcsin\left( \sin\frac{6\pi}{7} \right) =\]
\[= \arcsin\left( \sin\left( \pi - \frac{\pi}{7} \right) \right) =\]
\[= \arcsin\left( \sin\frac{\pi}{7} \right) = \frac{\pi}{7}\]
\[4)\arcsin\left( \sin 5 \right) =\]
\[= \arcsin\left( \sin(2\pi + 5 - 2\pi) \right) =\]
\[= \arcsin\left( \sin(5 - 2\pi) \right) = 5 - 2\pi\]