complex number

A complex number is a number of the form \(a+bi\), where \(a\) and \(b\) are both real numbers and \(i\) is the so-called imaginary number, that is, \(i^2=-1\).

The set of complex numbers is a field, and in particular is the algebraic closure of the real numbers.

Citation Info

  • [MLA] “complex number.” Platonic Realms Interactive Mathematics Encyclopedia. Platonic Realms, 25 Mar 2013. Web. 25 Mar 2013. <>
  • [APA] complex number (25 Mar 2013). Retrieved 25 Mar 2013 from the Platonic Realms Interactive Mathematics Encyclopedia:


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