Explicație pas cu pas:
[tex]0 < \frac{\pi}{12} < \frac{\pi}{2} = >I \\ [/tex]
[tex]\frac{5\pi}{3} = \frac{3\pi}{2} + \frac{1}{6} = > \\ \frac{3\pi}{2} < \frac{5\pi}{3} < 2\pi = > IV[/tex]
[tex]\frac{3\pi}{4} = \frac{\pi}{2} + \frac{1}{4} \\ \frac{\pi}{2} < \frac{3\pi}{4} \leqslant \pi = > II \\ [/tex]
[tex]\frac{11\pi}{12} = \frac{\pi}{2} + \frac{5\pi}{12} \\ \frac{\pi}{2} < \frac{11\pi}{12} \leqslant \pi = > II \\[/tex]
[tex]\frac{5\pi}{6} = \frac{\pi}{2} + \frac{\pi}{3} \\ \frac{\pi}{2} < \frac{5\pi}{6} \leqslant \pi = > II \\[/tex]
[tex]\frac{5\pi}{4} = \pi + \frac{\pi}{4} \\ \pi < \frac{5\pi}{4} \leqslant \frac{\pi}{2} = > III \\[/tex]
[tex]\frac{7\pi}{6} = \pi + \frac{\pi}{6} \\ \pi < \frac{7\pi}{6} \leqslant \frac{\pi}{2} = > III \\[/tex]
[tex]\frac{7\pi}{3} = 2\pi + \frac{\pi}{3} = > \\ 0 < \frac{\pi}{3} < \frac{\pi}{2} \\ \frac{7\pi}{3} = > I[/tex]
[tex]\frac{7\pi}{4} = \frac{3\pi}{2} + \frac{\pi}{4} = > \\ \frac{3\pi}{2} < \frac{7\pi}{4} < 2\pi = > IV[/tex]
[tex]\frac{11\pi}{6} = \frac{3\pi}{2} + \frac{\pi}{3} = > \\ \frac{3\pi}{2} < \frac{11\pi}{6} < 2\pi = > IV[/tex]
[tex]0 < \frac{5\pi}{12} < \frac{\pi}{2} = >I \\ [/tex]
[tex]\frac{7\pi}{12} = \frac{\pi}{2} + \frac{\pi}{12} \\ \frac{\pi}{2} < \frac{7\pi}{12} \leqslant \pi = > II \\[/tex]
[tex]\frac{5\pi}{3} = \frac{3\pi}{2} + \frac{\pi}{6} = > \\ \frac{3\pi}{2} < \frac{5\pi}{3} < 2\pi = > IV[/tex]
[tex]0 < \frac{\pi}{3} < \frac{\pi}{2} = >I \\ [/tex]
[tex]0 < \frac{\pi}{4} < \frac{\pi}{2} = >I \\ [/tex]
