complex number

American  

noun

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

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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

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complex number Scientific  

/ kŏm′plĕks′ /

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.

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Etymology

Origin of complex number

First recorded in 1825–35

Example Sentences

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

Solve the following equations over the complex number system.

From Textbooks • Dec. 1, 2021

To divide complex numbers, multiply both the numerator and denominator by the complex conjugate of the denominator to eliminate the complex number from the denominator.

From Textbooks • Dec. 1, 2021

Before multiplying, each square root of a negative number must be written as a complex number.

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