a)
\(sinx=sin\dfrac{\pi}{6}\\ < =>\left[{}\begin{matrix}x=\dfrac{\pi}{6}+k2\pi\\x=\pi-\dfrac{\pi}{6}+k2\pi\end{matrix}\right.\\ < =>\left[{}\begin{matrix}x=\dfrac{\pi}{6}+k2\pi\\x=\dfrac{5\pi}{6}+k2\pi\end{matrix}\right.\)
b)
\(sin2x=\dfrac{\sqrt{3}}{2}\\ < =>sin2x=sin\dfrac{\pi}{3}\\ < =>\left[{}\begin{matrix}2x=\dfrac{\pi}{3}+k2\pi\\2x=\pi-\dfrac{\pi}{3}+k2\pi\end{matrix}\right.\\ < =>\left[{}\begin{matrix}x=\dfrac{\pi}{6}+k\pi\\x=\dfrac{\pi}{3}+k\pi\end{matrix}\right.\)
c)
\(sin\left(x+\dfrac{\pi}{3}\right)=sin\left(2x-\dfrac{\pi}{4}\right)\\ < =>\left[{}\begin{matrix}x+\dfrac{\pi}{3}=2x-\dfrac{\pi}{4}+k2\pi\\x+\dfrac{\pi}{3}=\pi-2x+\dfrac{\pi}{4}+k2\pi\end{matrix}\right.\\ < =>\left[{}\begin{matrix}x=\dfrac{7\pi}{12}-k2\pi\\x=\dfrac{11\pi}{12}+k2\pi\end{matrix}\right.\)
(hiện tại mình vẫn đang trong quá trình làm nhưng do vấn đề thời gian nên mình tạm dừng tại đây)
