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complex number

American  

noun

  1. a mathematical expression (a +bi ) in which a and b are real numbers and i 2 = −1.


complex number British  

noun

  1. any number of the form a + i b , where a and b are real numbers and i = √–1 See number

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

complex number Scientific  
/ kŏmplĕks′ /
  1. A number that can be expressed in terms of i (the square root of −1). Mathematically, such a number can be written a + bi, where a and b are real numbers. An example is 4 + 5 i.


Etymology

Origin of complex number

First recorded in 1825–35

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

We had observed that, in such a scenario, which physicists call a quantum network, the Pál-Vértesi-McKague-Mosca-Gisin method could not reproduce the experimental outcomes predicted by complex number quantum theory.

From Scientific American • Apr. 24, 2023

To represent a complex number we need to address the two components of the number.

From Textbooks • Dec. 1, 2021

No. A complex number is not necessarily imaginary.

From Textbooks • Dec. 1, 2021

A complex number is of the form a + bi, where a, b are real numbers.

From Textbooks • May 6, 2020

The horizontal axis represents the real part of the complex number, while the vertical axis represents the imaginary part.

From "Zero: The Biography of a Dangerous Idea" by Charles Seife