[tex] \sin(x) = - 0.5 \\ \sin(x) = - \frac{1}{2} \\ x_{1} = - \frac{\pi}{6} + 2\pi n \: , \: n \: \epsilon \: z\\ x_{2} = \frac{7\pi}{6} + 2\pi n \: , \:n \: \epsilon \: z[/tex]