`#huy`
`2sin(4x-\pi/3)-1=0`
`<=>sin(4x-\pi/3)=1/2`
`<=>sin(4x-\pi/3)=`$\sin \dfrac{\pi}{6}$
`<=>`\(\left[ \begin{array}{l}4x-\dfrac{\pi}{3}=\dfrac{\pi}{6}+k2\pi\\4x-\dfrac{\pi}{3}=\dfrac{5\pi}{6}+k2\pi\end{array} \right.\) `<=>`\(\left[ \begin{array}{l}x=\dfrac{\pi}{8}+k\dfrac{\pi}{2}\\x=\dfrac{7\pi}{24}+k\dfrac{\pi}{2}\end{array} \right.\) `(k∈ZZ)`