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phương trình tương đương
$2-sin^22x=(3+\sqrt{3})sin2xcos2x+(2-3\sqrt{3})cos^22x$
$\Leftrightarrow sin^22x-(3+\sqrt{3})sin2xcos2x+3\sqrt{3}cos^22x=0$
$\Leftrightarrow (3cos2x-sin2x)(\sqrt{3}cos2x-sin2x)=0$
$\Leftrightarrow \left[ {\begin{matrix} 3cos2x-sin2x=0\\\sqrt{3}cos2x-sin2x=0\end{matrix}} \right.\Leftrightarrow\left[ {\begin{matrix} tan2x=3\\ tan2x=\sqrt{3} \end{matrix}} \right.\Leftrightarrow \left[ {\begin{matrix} x=\frac{1}{2}arctan(3)+\frac{k\pi }{2}\\ x=\frac{\pi }{6}+\frac{1}{2}k\pi \end{matrix}} \right. $
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