Past exam of the mathematics course of the year 1 of the natural sciences course of the University of Cambridge / 2007 / Paper 2 / Section A / 6

The two factors have moduli $\sqrt{2}$ and $2$, and complex arguments $\pi /4$ and $\pi /6$. Multiplication multiplies the moduli and adds the complex arguments, givingThe displayed angle is the principal argument in radians; equivalently the argument is $75^{\circ }$ modulo $360^{\circ }$.