\[\boxed{\mathbf{642}\mathbf{.}}\]
\[1)\sin x \bullet \sin{5x} = 1\]
\[Первая\ система:\]
\[\left\{ \begin{matrix} \sin x = 1\ \ \\ \sin{5x} = 1 \\ \end{matrix} \right.\ \text{\ \ }\]
\[\left\{ \begin{matrix} x = \arcsin 1 + 2\pi n\ \ \\ 5x = \arcsin 1 + 2\pi n \\ \end{matrix} \right.\ \]
\[\left\{ \begin{matrix} x = \frac{\pi}{2} + 2\pi n\ \ \\ 5x = \frac{\pi}{2} + 2\pi n \\ \end{matrix} \right.\ \]
\[\left\{ \begin{matrix} x = \frac{\pi}{2} + 2\pi n\ \ \\ x = \frac{\pi}{10} + \frac{2\pi n}{5} \\ \end{matrix} \right.\ \text{\ \ }\]
\[x = \frac{\pi}{2} + 2\pi n.\]
\[Вторая\ система:\]
\[\left\{ \begin{matrix} \sin x = - 1\ \ \\ \sin{5x} = - 1 \\ \end{matrix} \right.\ \text{\ \ }\]
\[\left\{ \begin{matrix} x = - \arcsin 1 + 2\pi n\ \ \\ 5x = - \arcsin 1 + 2\pi n \\ \end{matrix} \right.\ \text{\ \ \ }\]
\[\left\{ \begin{matrix} x = - \frac{\pi}{2} + 2\pi n\ \ \\ 5x = - \frac{\pi}{2} + 2\pi n \\ \end{matrix} \right.\ \]
\[\left\{ \begin{matrix} x = - \frac{\pi}{2} + 2\pi n\ \ \\ x = - \frac{\pi}{10} + \frac{2\pi n}{5} \\ \end{matrix} \right.\ \]
\[x = - \frac{\pi}{2} + 2\pi n.\]
\[Ответ:\ \ \frac{\pi}{2} + \pi n.\]
\[2)\sin x \bullet \cos{4x} = - 1\]
\[Первая\ система:\]
\[\left\{ \begin{matrix} \sin x = 1\ \ \ \ \ \ \\ \cos{4x} = - 1 \\ \end{matrix} \right.\ \text{\ \ \ }\]
\[\left\{ \begin{matrix} x = \arcsin 1 + 2\pi n\ \ \ \ \ \ \ \ \ \ \ \\ 4x = \pi - \arccos 1 + 2\pi n \\ \end{matrix} \right.\ \text{\ \ \ }\]
\[\left\{ \begin{matrix} x = \frac{\pi}{2} + 2\pi n\ \ \\ 4x = \pi + 2\pi n \\ \end{matrix} \right.\ \]
\[\left\{ \begin{matrix} x = \frac{\pi}{2} + 2\pi n \\ x = \frac{\pi}{4} + \frac{\text{πn}}{2}\text{\ \ \ } \\ \end{matrix} \right.\ \text{\ \ \ }\]
\[корней\ нет.\]
\[Вторая\ система:\]
\[\left\{ \begin{matrix} \sin x = - 1 \\ \cos{4x} = 1 \\ \end{matrix} \right.\ \text{\ \ \ }\]
\[\left\{ \begin{matrix} x = - \arcsin 1 + 2\pi n \\ 4x = \arccos 1 + 2\pi n\ \\ \end{matrix} \right.\ \text{\ \ \ }\]
\[\left\{ \begin{matrix} x = - \frac{\pi}{2} + 2\pi n\ \ \\ 4x = 2\pi n\ \ \ \ \ \ \ \ \ \ \ \ \\ \end{matrix} \right.\ \]
\[\left\{ \begin{matrix} x = - \frac{\pi}{2} + 2\pi n \\ x = \frac{\text{πn}}{2}\text{\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ } \\ \end{matrix} \right.\ \text{\ \ }\]
\[x = - \frac{\pi}{2} + 2\pi n.\]
\[Ответ:\ \ - \frac{\pi}{2} + 2\pi n.\]