# imaginary number

imaginary number
Also called imaginary, pure imaginary number. a complex number having its real part equal to zero.
[1905-10]

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Any number of the form a + bi where a and b are real numbers, i is the square root of -1, and b is not zero.

If a is zero, the number is called a pure imaginary number. See also complex number.

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any product of the form ai, in which a is a real number and i is the imaginary unit defined as √(−1) . See numerals and numeral systems.

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Universalium. 2010.

### Look at other dictionaries:

• imaginary number — n. a complex number in the form a + bi where b is not zero: when a is zero, it is a pure imaginary number …   English World dictionary

• Imaginary Number —   [dt. »imaginäre Zahl«], komplexe Zahlen …   Universal-Lexikon

• Imaginary number — In mathematics, an imaginary number (or purely imaginary number) is a complex number whose squared value is a real number not greater than zero.Ahlfors, Lars V. Complex Analysis. 3rd Ed. New York: McGraw Hill, 1979. Pages 1 4.] The imaginary unit …   Wikipedia

• imaginary number — noun (mathematics) a number of the form a+bi where a and b are real numbers and i is the square root of 1 • Syn: ↑complex number, ↑complex quantity, ↑imaginary • Topics: ↑mathematics, ↑math, ↑maths …   Useful english dictionary

• imaginary number — noun A number of the form ai, where a is a real number and i = minus;1; a complex number whose real part is zero. Syn: purely imaginary number …   Wiktionary

• imaginary number — /ɪˌmædʒənəri ˈnʌmbə/ (say i.majuhnuhree numbuh) noun the square root of a negative number; thus √ ̅1̅ is an imaginary number, denoted by i, and so i2 = 1 …

• imaginary number — noun Date: circa 1911 a complex number (as 2 + 3i) in which the coefficient of the imaginary unit is not zero called also imaginary compare pure imaginary …   New Collegiate Dictionary

• imaginary number — imag′inary num′ber n. math. a complex number having its real part equal to zero • Etymology: 1905–10 …   From formal English to slang

• pure imaginary number — noun an imaginary number of the form a+bi where a is 0 • Hypernyms: ↑complex number, ↑complex quantity, ↑imaginary number, ↑imaginary • Hyponyms: ↑imaginary part, ↑imaginary part of a complex number * * * Math …   Useful english dictionary

• purely imaginary number — noun An imaginary number …   Wiktionary