Answer:
[tex]\dfrac{z_1}{z_2}=\dfrac{1}{2}\,\text{cis}\,\dfrac{7\pi}{12}[/tex]
Step-by-step explanation:
The quotient of complex numbers is the quotient of their magnitudes at the difference of their angles.
[tex]\dfrac{z_1}{z_2}=\dfrac{\text{cis}\,\dfrac{2\pi}{3}}{2\,\text{cis}\,\dfrac{\pi}{12}}=\dfrac{1}{2}\,\text{cis}\left(\dfrac{2\pi}{3}-\dfrac{\pi}{12}\right)\\\\\bf{\dfrac{z_1}{z_2}=\dfrac{1}{2}\,\text{cis}\,\dfrac{7\pi}{12}}[/tex]
