Polar Form
A Complex Number z can be specified by using Polar Coordinates. The representation of a complex number by its polar coordinates is called the Polar Form of the complex number.
Polar Form Notation
Trigonometric Form of Polar Form Notation:
- $ z = r\,(\cos \varphi + i\sin \varphi )\, $
Exponential Form of Polar Form Notation:
- $ z = r\,\mathrm{e}^{i \varphi}\, $
Source
http://en.wikipedia.org/wiki/Complex_number#Absolute_value.2C_conjugation_and_distance