翻訳と辞書
Words near each other
・ Frog Fire
・ Frog Fractions
・ Frog hearing and communication
・ Frog Hill View Point
・ Frobisher, Saskatchewan
・ Frobot
・ Frocester
・ Frocester railway station
・ Frock
・ Frock coat
・ Frock Me
・ Frock Me!
・ Frocking
・ Frocktober
・ Frocourt
Froda's theorem
・ Frode Alnæs
・ Frode Andresen
・ Frode Barth
・ Frode Berg
・ Frode Berge
・ Frode Bovim
・ Frode Eike Hansen
・ Frode Elsness
・ Frode Estil
・ Frode Fjellheim
・ Frode Fjerdingstad
・ Frode Flesjå
・ Frode Gjerstad
・ Frode Glesnes


Dictionary Lists
翻訳と辞書 辞書検索 [ 開発暫定版 ]
スポンサード リンク

Froda's theorem : ウィキペディア英語版
Froda's theorem

In mathematics, Darboux-Froda's theorem, named after Alexandru Froda, a Romanian mathematician, describes the set of discontinuities of a (monotone) real-valued function of a real variable. Usually, this theorem appears in literature without a name. It was written in A. Froda' thesis in 1929 .〔Alexandru Froda, (Sur la Distribution des Propriétés de Voisinage des Fonctions de Variables Réelles ), These, Harmann, Paris, 3 December 1929〕〔''Alexandru Froda – Collected Papers (Opera Matematica), Vol.1'', Ed. Academ. Romane, 2000〕. As it is acknowledged in the thesis, it is in fact due Jean Gaston Darboux 〔 Jean Gaston Darboux (Mémoire sur les fonctions discontinues ), Annales
de l'École Normale supérieure, 2-ème série, t. IV, 1875, Chap VI. 〕
==Definitions==
#Consider a function of real variable with real values defined in a neighborhood of a point x_0 and the function is discontinuous at the point on the real axis x = x_0. We will call a removable discontinuity or a jump discontinuity a discontinuity of the first kind.〔Walter Rudin, ''Principles of Mathematical Analysis'', McGraw-Hill 1964, (Def. 4.26, pp. 81–82)〕
#Denote f(x+0):=\lim_f(x+h) and f(x-0):=\lim_f(x-h). Then if f(x_0+0) and f(x_0-0) are finite we will call the difference f(x_0+0)-f(x_0-0) the jump〔M. Nicolescu, N. Dinculeanu, S. Marcus, ''Mathematical Anlaysis'' (Bucharest 1971), Vol.1, Pg.213, (Romanian )〕 of f at x_0.
If the function is continuous at x_0 then the jump at x_0 is zero. Moreover, if f is not continuous at x_0, the jump can be zero at x_0 if f(x_0+0)=f(x_0-0)\neq f(x_0).

抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)
ウィキペディアで「Froda's theorem」の詳細全文を読む



スポンサード リンク
翻訳と辞書 : 翻訳のためのインターネットリソース

Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.