ĐKXĐ: \(-3\le x\le1\)
\(\sqrt{3-3x}=2+\sqrt{3+x}\)
\(\Leftrightarrow3-3x=4+3+x+4\sqrt{3+x}\)
\(\Leftrightarrow-1-x=\sqrt{3+x}\)
\(\Leftrightarrow\left\{{}\begin{matrix}-1-x\ge0\\\left(-1-x\right)^2=3+x\end{matrix}\right.\) \(\Leftrightarrow\left\{{}\begin{matrix}x\le-1\\x^2+x-2=0\end{matrix}\right.\) \(\Rightarrow x=-2\)