[latex]cos \frac{ \pi (x-2)}{3} = \frac{1}{2} [/latex]

[latex]cos \frac{\pi (x-2)}{3}=\frac{1}{2}\\\\\frac{\pi (x-2)}{3}=\pm \frac{\pi}{3}+2\pi n \; ,\; n\in Z\\\\x-2=\pm \frac{\pi}{3}\cdot \frac{3}{\pi}+\frac{6\pi n}{\pi }=\pm 1+6n\; ,\; n\in Z\\\\x=\pm 1+2+6n= \left [ {{3+6n=3(2n+1)} \atop {1+6n\; ,\; n\in Z}} \right. [/latex]