Hostname: page-component-586b7cd67f-2brh9 Total loading time: 0 Render date: 2024-11-24T18:58:48.691Z Has data issue: false hasContentIssue false

Functions which permute the roots of an equation

Published online by Cambridge University Press:  22 September 2016

F. J. Budden*
Affiliation:
Royal Grammar School, Newcastle upon Tyne

Extract

An amusing exercise to give to a mathematical sixth form is:

If the roots of the equation

F1(x) ≡ x3 + x2 − 2x − 1 = 0 (1)

are α, β, γ, form the equation whose roots are α2 − 2, β2 − 2, γ2 − 2.

The usual methods used will be, either to find the coefficients of the new equation by forming the appropriate symmetric functions of α, β, γ; or else to eliminate x from the relation y = x2 – 2 and the given cubic equation.

Type
Research Article
Copyright
Copyright © Mathematical Association 1976

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)