Question

\(\sqrt{3}c\text{os}3x+sin3x=0\)

Answer 1

\(\Leftrightarrow\dfrac{\sqrt{3}}{2}cos3x+\dfrac{1}{2}sin3x=0\)

\(\Leftrightarrow sin\left(3x+\dfrac{\pi}{3}\right)=0\)

\(\Leftrightarrow3x+\dfrac{\pi}{3}=k\pi\)

\(\Leftrightarrow x=-\dfrac{\pi}{9}+\dfrac{k\pi}{3}\)