## Precalculus (6th Edition) Blitzer

The given statement shows that the equation of $\cos \frac{x}{3}=\frac{1}{2}$ indicates that $\frac{x}{3}=\frac{\pi }{3}+2n\pi \,or\,\frac{x}{3}=\frac{5\pi }{3}+2n\pi$. Thus, this statement is true because $\frac{x}{3}$ can be written as $\frac{\pi }{3}+2n\pi$ and it can also be written as $\frac{5\pi }{3}+2n\pi$.