imaginary number

noun — 2 senses

imaginary number

noun

Etymology The adjective imaginary in this context was first used (as French imaginaire) by René Descartes in 1673, La Geometrie, referring to imaginary numbers in the broad sense, as non-real roots of polynomials. Descartes' usage was derogatory, but the concept later gained acceptance through the work of Leonhard Euler and Carl Friedrich Gauss in the 18th century.

1

Complex analysis, Mathematics, Sciences Strict sense A number of the form bi, where b is any real number and i denotes the imaginary unit.

  • If a#61;0, then x#61;ib is called an imaginary number. The message here is that we must introduce imaginary numbers in order to be able to solve quadratic equations in general.2008, Donald A. McQuarrie, Mathematics for Physical Chemistry: Opening Doors, University Science Books, page 54:
2

Complex analysis, Mathematics, Sciences Broadly A number of the form a + bi, where a and b are real numbers and b is nonzero.

Synonyms
purely imaginary number
Related terms
complex number, real number
Hypernyms
complex number
Hyponyms
purely imaginary number, pure imaginary number

Entry derived from the Wiktionary, under licence CC BY-SA 4.0 — list of authors.