| Share
 

root

root, in mathematics, number or quantity r for which an equation f ( r ) = 0 holds true, where f is some function. If f is a polynomial, r is called a root of f; for example, r = 3 and r = - 4 are roots of the equation x 2+ x - 12 = 0, because (3)2+(3) - 12 = 0 and ( - 4)2+( - 4) - 12 = 0. In the special case where f ( x ) = x n - a for some number a, a root of f is called an n th root of a, denoted by n a art/nth-root-of-a.gif or a 1/ n . For example, 2 is the third, or cube, root of 8 (38art/cube-root-of-8.gif = 2), since it satisfies the equation x 3 - 8 = 0. Every number has n different (real or complex) n th roots; e.g., there are two square roots of 9 (3 and - 3) since (3)(3) = 9 and ( - 3)( - 3) = 9.

The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved.

See more Encyclopedia articles on: Mathematics


Premium Partner Content
HighBeam Research
Documents Images and Maps Reference
(from Newspapers, Magazines, Journals, Newswires, Transcripts and Books)

Research our extensive archive of more than 80 million articles from 6,500 publications.

Additional search results provided by HighBeam Research, LLC. © Copyright 2005. All rights reserved.

24 X 7

Private Tutor

Click Here for Details
24 x 7 Tutor Availability
Unlimited Online Tutoring
1-on-1 Tutoring
Expert Tutors for Math Help & Algebra Help