Đáp án + Giải thích các bước giải:
`sin (3x+1) =1/2`
`<=>sin(3x+1)=sin(pi/6)`
`<=>`\(\left[ \begin{array}{l}3x+1=\dfrac{\pi}{6}+k2\pi\\3x+1=\pi-\dfrac{\pi}{6}+k2\pi\end{array} \right.\)
`<=>`\(\left[ \begin{array}{l}3x=\dfrac{\pi}{6}-1+k2\pi\\3x=\dfrac{5\pi}{6}-1+k2\pi\end{array} \right.\)
`<=>`\(\left[ \begin{array}{l}x=\dfrac{\pi}{18}-\dfrac{1}{3}+\dfrac{k2\pi}{3}\\x=\dfrac{5\pi}{18}-\dfrac{1}{3}+\dfrac{k2\pi}{3}\end{array} \right.\)`(kinZZ)`
