# complex number

- a mathematical expression (a + bi) in which a and b are real numbers and i2 = −1.

## Origin of complex number^{}

First recorded in 1825–35

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# complex number

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

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# complex number

[kŏm′plĕks′]

- 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 + 5i.

The American Heritage® Science Dictionary
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