Запиши формулы серий точек, обозначенных на рисунке

• \(\cfrac{\pi}{4}\)
• \(2\pi k\)
• \(\cfrac{\pi}{8}\)
• \(\pi k\)
• \(-\cfrac{\pi}{4}\)
• \(2\pi n\)
• \(-\cfrac{\pi}{2}\)
• \(\pi n\)
• \(\cfrac{\pi}{2}\)
• \(\pi k\)

1. \(P\) и \(P\_1\) : [ ] \(+\) [ ], \(k\in \Z\) .
2. \(Q\) и \(Q\_1\) : [ ] \(+\) [ ], \(n\in \Z\) .
3. \(R\) и \(R\_1\) : [ ] \(+\) [ ], \(k\in \Z\) .