\(\Leftrightarrow sinx+sinax=\sqrt{3}cosx-\sqrt{3}cosax\)
\(\Leftrightarrow sinax+\sqrt{3}cosax=\sqrt{3}cosx-sinx\)
\(\Leftrightarrow\dfrac{\sqrt{3}}{2}cosax+\dfrac{1}{2}sinax=\dfrac{\sqrt{3}}{2}cosx-\dfrac{1}{2}sinx\)
\(\Leftrightarrow cos\left(ax-\dfrac{\pi}{6}\right)=cos\left(x+\dfrac{\pi}{6}\right)\)
\(\Leftrightarrow\left[{}\begin{matrix}ax-\dfrac{\pi}{6}=x+\dfrac{\pi}{6}+k2\pi\\ax-\dfrac{\pi}{6}=-x-\dfrac{\pi}{6}+k2\pi\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}\left(a-1\right)x=\dfrac{\pi}{3}+k2\pi\\\left(a+1\right)x=k2\pi\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{\pi}{3\left(a-1\right)}+\dfrac{k2\pi}{a-1}\left(a\ne1\right)\\x=\dfrac{k2\pi}{a+1}\left(a\ne-1\right)\end{matrix}\right.\)