Toán √3sinx-cox3x=-2 có cao nhân nào không ạ? 13/09/2021 By Nevaeh √3sinx-cox3x=-2 có cao nhân nào không ạ?
$\dfrac{\sqrt3}{2}\sin 3x-\dfrac{1}{2}\cos 3x=-1$ $\Rightarrow \sin(3x-\dfrac{\pi}{6})=-1$ $\Rightarrow 3x-\dfrac{\pi}{6}=\dfrac{-\pi}{2}+k2\pi$ $\Rightarrow x=\dfrac{-\pi}{9}+k\dfrac{2\pi}{3}$ Trả lời
$\dfrac{\sqrt3}{2}\sin 3x-\dfrac{1}{2}\cos 3x=-1$
$\Rightarrow \sin(3x-\dfrac{\pi}{6})=-1$
$\Rightarrow 3x-\dfrac{\pi}{6}=\dfrac{-\pi}{2}+k2\pi$
$\Rightarrow x=\dfrac{-\pi}{9}+k\dfrac{2\pi}{3}$