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Câu hỏi: Phương trình $2\sin x-\sqrt{3}=0$ có tập nghiệm là
A. $\left\{ \pm \dfrac{\pi }{3}+k2\pi ,k\in \mathbb{Z} \right\}$.
B. $\left\{ \dfrac{\pi }{3}+k2\pi ,\dfrac{2\pi }{3}+k2\pi ,k\in \mathbb{Z} \right\}$.
C. $\left\{ \dfrac{\pi }{6}+k2\pi ,\dfrac{5\pi }{6}+k2\pi ,k\in \mathbb{Z} \right\}$.
D. $\left\{ \pm \dfrac{\pi }{6}+k2\pi ,k\in \mathbb{Z} \right\}$.
A. $\left\{ \pm \dfrac{\pi }{3}+k2\pi ,k\in \mathbb{Z} \right\}$.
B. $\left\{ \dfrac{\pi }{3}+k2\pi ,\dfrac{2\pi }{3}+k2\pi ,k\in \mathbb{Z} \right\}$.
C. $\left\{ \dfrac{\pi }{6}+k2\pi ,\dfrac{5\pi }{6}+k2\pi ,k\in \mathbb{Z} \right\}$.
D. $\left\{ \pm \dfrac{\pi }{6}+k2\pi ,k\in \mathbb{Z} \right\}$.
$2\sin x-\sqrt{3}=0\Leftrightarrow \sin x=\dfrac{\sqrt{3}}{2}\Leftrightarrow \sin x=\sin \dfrac{\pi }{3}$ $\Leftrightarrow \left[ \begin{aligned}
& x=\dfrac{\pi }{3}+k2\pi \\
& x=\dfrac{2\pi }{3}+k2\pi \\
\end{aligned} \right.(k\in \mathbb{Z})$.
& x=\dfrac{\pi }{3}+k2\pi \\
& x=\dfrac{2\pi }{3}+k2\pi \\
\end{aligned} \right.(k\in \mathbb{Z})$.
Đáp án B.