Encyclopedia > Imaginary numbers

  Article Content

Imaginary number

Redirected from Imaginary numbers

An imaginary number is a number whose square is negative. The term was coined by René Descartes in the seventeenth century and was meant to be derogatory: obviously such numbers don't exist. Nowadays we find the imaginary numbers on the vertical axis of the complex number plane. Every imaginary number can be written as <math>ib</math> where <math>b</math> is a real number and <math>i</math> the imaginary unit with the property that

<math>i^2 = -1.</math>
(In electrical engineering and related fields, the imaginary unit is often written as <math>j</math> to avoid confusion with a changing current, traditionally denoted by <math>i</math>.) Every complex number can be written uniquely as a sum of a real number and an imaginary number.

See also



All Wikipedia text is available under the terms of the GNU Free Documentation License

 
  Search Encyclopedia

Search over one million articles, find something about almost anything!
 
 
  
  Featured Article
East Islip, New York

... is 1,322.5/km² (3,428.5/mi²). There are 4,661 housing units at an average density of 437.9/km² (1,135.1/mi²). The racial makeup of the town is 96.20% ...

 
 
 
This page was created in 38.7 ms