TeX Quellcode:

{z_1\cdot z_2 = 3\left(\cos\left(\dfrac{\pi}{3}\right)+i\sin\left(\dfrac{\pi}{3}\right)\right)\cdot\dfrac{1}{4}\left(\cos\left(\dfrac{5\pi}{9}\right)+i\sin\left(\dfrac{5\pi}{9}\right)\right)=3\cdot \dfrac{1}{4}\left(\cos\left(\dfrac{\pi}{3}+\dfrac{5\pi}{9}\right)+i\sin\left(\dfrac{\pi}{3}+\dfrac{5\pi}{9}\right)\right) = \dfrac{3}{4}\left(\cos\left(\dfrac{8\pi}{9}\right)+i\sin\left(\dfrac{8\pi}{9}\right)\right)}