imaginary unit

The imaginary unitMathworldPlanetmath i:=-1. Any imaginary numberMathworldPlanetmath m may be written as m=bi, b. Any complex numberMathworldPlanetmathPlanetmath c may be written as c=a+bi, a,b.

Note that there are two complex square roots of -1 (i.e. the two solutions to the equation x2+1=0 in ), so there is always some ambiguity in which of these we choose to call “i” and which we call “-i”, though this has little bearing on any applications of complex numbers.

In physics and some engineering fields, the symbol j is used for the imaginary unit.

Title imaginary unit
Canonical name ImaginaryUnit
Date of creation 2013-03-22 12:21:14
Last modified on 2013-03-22 12:21:14
Owner Mathprof (13753)
Last modified by Mathprof (13753)
Numerical id 10
Author Mathprof (13753)
Entry type Definition
Classification msc 12D99
Synonym i
Related topic Imaginary
Related topic Complex