1) \cos\alpha=\dfrac{\sqrt{2}}{2}; 2) \cos \alpha =\dfrac{1}{2}. \pm \dfrac{\pi}{4} 2\pi n \pm \dfrac{\pi}{3} 2\pi m \dfrac{\pi}{4} \dfrac{\pi}{6} \pi k \pi m Ответ: 1) \alpha=+, n\in \Z; 2) \alpha=+, m\in \Z.

Задание

Реши уравнения

\(\cos\alpha=\dfrac{\sqrt{2}}{2}\) ;

\(\cos \alpha =\dfrac{1}{2}\) .

\(\pm \dfrac{\pi}{4}\)
\(2\pi n\)
\(\pm \dfrac{\pi}{3}\)
\(2\pi m\)
\(\dfrac{\pi}{4}\)
\(\dfrac{\pi}{6}\)
\(\pi k\)
\(\pi m\)

Ответ:

\(\alpha=\) [ ] \(+\) [ ], \(n\in \Z\) ;
\(\alpha=\) [ ] \(+\) [ ], \(m\in \Z\) .