Đáp án: \(\left[ \begin{array}{l}x=k2\pi\\x=\dfrac{\pi}{3}+\dfrac{k2\pi}{3}\end{array} \right.\)
Giải thích các bước giải:
$sin2x=sinx$
⇔ \(\left[ \begin{array}{l}2x=x+k2\pi\\2x=\pi-x+k2\pi\end{array} \right.\)
⇔ \(\left[ \begin{array}{l}x=k2\pi\\3x=\pi+k2\pi\end{array} \right.\)
⇔ \(\left[ \begin{array}{l}x=k2\pi\\x=\dfrac{\pi}{3}+\dfrac{k2\pi}{3}\end{array} \right.\) $(k∈\mathbb{Z})$
