\(\Leftrightarrow1-sin^22x-3sin2x-3=0\)
\(\Leftrightarrow sin^22x+3sin2x+2=0\)
\(\Rightarrow\left[{}\begin{matrix}sin2x=-1\\sin2x=-2< -1\left(loại\right)\end{matrix}\right.\)
\(\Rightarrow2x=-\dfrac{\pi}{2}+k2\pi\)
\(\Rightarrow x=-\dfrac{\pi}{4}+k\pi\)