$$\lceil\ \frac{-\pi}{3}+2\pi n;\frac{\pi}{3}+2\pi n\text{}\rceil,n\in Z$$  

$$\lceil\ \frac{\pi}{6}+2\pi n;\frac{11\pi}{6}+2\pi n\rceil,n\in Z$$  

$$\lceil\ \frac{-\pi}{6}+2\pi n;\frac{\pi}{6}+2\pi n\rceil,n\in Z$$  

$$\left(\pi n;\frac{\pi}{6}+\pi n\right),n\in Z$$  

$$\left(\frac{\pi}{6}+\pi n;\frac{\pi}{2}+\pi n\right),n\in Z$$  

$$\left(\frac{\pi}{6}+\pi n;\ \pi+\pi n\right),n\in Z$$  

$$\left(-\frac{\pi}{18}+\frac{2\pi k}{3};\frac{7\pi}{18}+\frac{2\pi k}{3}\right)$$  

$$\left(-\frac{\pi}{6}+\frac{2\pi k}{3};\frac{7\pi}{6}+\frac{2\pi k}{3}\right)$$  

$$\left(-\frac{\pi}{18}+2\pi k;\frac{7\pi}{18}+2\pi k\right)$$  

$$\left(-\frac{5\pi}{6}+2\pi k;\frac{5\pi}{6}+2\pi k\right)$$  

$$\left(\frac{\pi}{12}+2\pi k;\frac{5\pi}{12}+2\pi k\right)$$  

$$\left(-\frac{13\pi}{12}+2\pi n;\ \frac{7\pi}{12}+2\pi n\right)$$  

$$\left(\frac{\pi}{4}+2\pi k;\frac{7\pi}{4}+2\pi k\right)$$  

$$\left(\frac{\pi}{2}+4\pi k;\frac{7\pi}{2}+4\pi k\right)$$  

$$\left(\frac{\pi}{2}+2\pi k\text{;}\frac{7\pi}{2}+2\pi k\right)$$  

$$\left(-\frac{\pi}{4}+\frac{\pi k}{2};-\frac{\pi}{8}+\frac{\pi k}{2}\right)$$  

$$\left(-\frac{\pi}{2}+\frac{\pi k}{2};-\frac{\pi}{4}+\frac{\pi k}{2}\right)$$  

$$\left(-\frac{\pi}{4}+\pi k;-\frac{\pi}{8}+\pi k\right)$$