Vol. 27, No. 1, 1968

Download this article
Download this article. For screen
For printing
Recent Issues
Vol. 332: 1  2
Vol. 331: 1  2
Vol. 330: 1  2
Vol. 329: 1  2
Vol. 328: 1  2
Vol. 327: 1  2
Vol. 326: 1  2
Vol. 325: 1  2
Online Archive
Volume:
Issue:
     
The Journal
About the journal
Ethics and policies
Peer-review process
 
Submission guidelines
Submission form
Editorial board
Officers
 
Subscriptions
 
ISSN 1945-5844 (electronic)
ISSN 0030-8730 (print)
 
Special Issues
Author index
To appear
 
Other MSP journals
A theorem of Rolle’s type in En for functions of the class C1

G. P. Szegő

Vol. 27 (1968), No. 1, 193–195
Abstract

In a note recently published W. Leighton presents the following theorem.

Theorem 1. Let f(x) = (x1,,xn) be of class C2 in En. Suppose that f(x) has an isolated relative minimum at x = 0, and that f(0) = 0. If there is a point x = 0 where f(x) = 0, then f(x) must have at least one critical point, finite or infinite, in addition to that at the origin.

The proof employed by Prof. Leighton of Theorem (1) is based upon the theory of Morse and for this the condition that f(x) belongs to class C2 is essential.

In what follows we shall give a proof of Theorem (1) for functions of class C1.

Mathematical Subject Classification
Primary: 49.10
Secondary: 26.00
Milestones
Received: 10 May 1967
Revised: 24 November 1967
Published: 1 October 1968
Authors
G. P. Szegő