giúp em với : sin ( 2x - pi / 6 ) = 1 / 2

`~rai~`

\(\sin\left(2x-\dfrac{\pi}{6}\right)=\dfrac{1}{2}\\\Leftrightarrow \left[\begin{array}{I}2x-\dfrac{\pi}{6}=\dfrac{\pi}{6}+k2\pi\\2x-\dfrac{\pi}{6}=\pi-\dfrac{\pi}{6}+k2\pi\end{array}\right.\\\Leftrightarrow \left[\begin{array}{I}2x=\dfrac{\pi}{6}+\dfrac{\pi}{6}+k2\pi\\2x=\pi-\dfrac{\pi}{6}+\dfrac{\pi}{6}+k2\pi\end{array}\right.\\\Leftrightarrow \left[\begin{array}{I}2x=\dfrac{\pi}{3}+k2\pi\\2x=\pi+k2\pi\end{array}\right.\\\Leftrightarrow \left[\begin{array}{I}x=\dfrac{\pi}{6}+k2\pi\\x=\dfrac{\pi}{2}+k\pi.\end{array}\right.\quad(k\in\mathbb{Z})\\\text{Vậy phương trình có các họ nghiệm là:}\\x=\dfrac{\pi}{6}+k\pi;x=\dfrac{\pi}{2}+k\pi.(k\in\mathbb{Z})\)