giải phương trình sin(2x+30°)=1/2

$\begin{array}{l}
\sin \left( {2x + {{30}^o}} \right) = \dfrac{1}{2}\\
 \Leftrightarrow \sin \left( {2x + {{30}^o}} \right) = \sin {30^o}\\
 \Leftrightarrow \left[ \begin{array}{l}
2x + {30^o} = {30^o} + k{360^o}\\
2x + {30^o} = {180^o} - {30^o} + k{360^o}
\end{array} \right.\\
 \Leftrightarrow \left[ \begin{array}{l}
x = k{180^o}\\
x = {60^o} + k{180^o}
\end{array} \right.\left( {k \in \mathbb Z} \right)
\end{array}$