Asosiy tarkibga o'tish

1.3-bo'lim : Trig funktsiyalari

10. Kalkulyatordan foydalanmasdan \(\displaystyle \sin \left( { - \frac{{11\pi }}{3}} \right)\) ning aniq qiymatini aniqlang.

Yechim

Avval biz \(\frac{\pi }{3} - 4\pi = - \frac{{11\pi }}{3}\) ekanligini va \(4\pi \) ikkita to'liq aylanish ekanligini ta'kidlaymiz (shuningdek, manfiy burchaklar soat yo'nalishi bo'yicha aylantirilishini yodda tutsak) biz \( - \frac{{11\pi }}{3}\) va \(\frac{\pi }{3}\) uchun terminal chizig'i bir xil burchak ekanligini ko'rishimiz mumkin va shuning uchun biz ushbu muammo uchun quyidagi birlik doirasiga ega bo'lamiz.

A unit circle with the angles \(\frac{\pi }{6}\), \(\frac{\pi }{4}\) and \(\frac{\pi }{3}\) drawn in the first quadrant and labeled with the coordinates \(\left( {\frac{{\sqrt 3 }}{2},\frac{1}{2}} \right)\), \(\left( {\frac{{\sqrt 2 }}{2},\frac{{\sqrt 2 }}{2}} \right)\) and \(\left( {\frac{1}{2},\frac{{\sqrt 3 }}{2}} \right)\) where they meet the circle.  The axes are labeled with the angles 0 and \(2\pi \), \(\frac{\pi }{2}\), \(\pi \) and \(\frac{{3\pi }}{2}\) and the points (1,0), (0,1), (-1,0) and (0,-1).  The line for the angle \(\frac{\pi }{3}\) is also labeled \( - \frac{{11\pi }}{3}\), showing that the two angles end on the same line.
2-qadam

\( - \frac{{11\pi }}{3}\) va \(\frac{\pi }{3}\) bir xil burchak bo'lgani uchun javob:

\[\sin \left( { - \frac{{11\pi }}{3}} \right) = \frac{{\sqrt 3 }}{2}\]