Giải phương trình 2 sin x − 1 = 0 .

\[2\sin x - 1 = 0 \Leftrightarrow \sin x = \frac{1}{2}\]\[\begin{array}{l} \Leftrightarrow \sin x = \sin \frac{\pi }{6}\\ \Leftrightarrow \left[ \begin{array}{l}x = \frac{\pi }{6} + 2k\pi \\x = \frac{{5\pi }}{6} + 2k\pi \end{array} \right.,k \in \mathbb{Z}\end{array}\]