Решебник по алгебре и начала математического анализа 11 класс Колягин Задание 29

\[y = \cos\left( x + \frac{\pi}{3} \right);\ \ \ x = a.\]

\[1)\ a = \frac{\pi}{6}:\]

\[\cos\left( \frac{\pi}{6} + \frac{\pi}{3} \right) = \cos\frac{3\pi}{6} = \cos\frac{\pi}{2} = 0;\]

\[2)\ a = \frac{\pi}{3}:\]

\[\cos\left( \frac{\pi}{3} + \frac{\pi}{3} \right) = \cos\frac{2\pi}{3} = - \frac{1}{2};\]

\[3)\ a = \frac{\pi}{2}:\]

\[\cos\left( \frac{\pi}{2} + \frac{\pi}{3} \right) = \cos\frac{5\pi}{6} = - \frac{\sqrt{3}}{2};\]

\[4)\ a = \frac{7\pi}{6}:\]

\[\cos\left( \frac{7\pi}{6} + \frac{\pi}{3} \right) = \cos\frac{9\pi}{6} =\]

\[= \cos\frac{3\pi}{2} = 0.\]