**i**which is defined as solution of sqrt(-1).If real numbers are thought as a line of infinite length, then the

**imaginary numbers**(multiples of

**i**) are on a line by the location of 0 on real numbers' line, rotated by pi/4 (or 90 degrees). Both lines define a

**plane**of complex numbers. A complex number can hence be imagined as a pair of

{real imaginary}components.DKF: They can also be described using "polar coordinates" (i.e. angle and magnitude) which is a format that makes multiplication, division, exponentiation and (simple) root-finding much simpler.

See also