Superstability of Generalized Multiplicative Functionals

<p/> <p>Let <inline-formula> <graphic file="1029-242X-2009-486375-i1.gif"/></inline-formula> be a set with a binary operation <inline-formula> <graphic file="1029-242X-2009-486375-i2.gif"/></inline-formula> such that, for each <i...

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Bibliographic Details
Main Authors: Takagi Hiroyuki, Tsukada Makoto, Miura Takeshi, Takahasi Sin-Ei
Format: Article
Language:English
Published: SpringerOpen 2009-01-01
Series:Journal of Inequalities and Applications
Online Access:http://www.journalofinequalitiesandapplications.com/content/2009/486375
Description
Summary:<p/> <p>Let <inline-formula> <graphic file="1029-242X-2009-486375-i1.gif"/></inline-formula> be a set with a binary operation <inline-formula> <graphic file="1029-242X-2009-486375-i2.gif"/></inline-formula> such that, for each <inline-formula> <graphic file="1029-242X-2009-486375-i3.gif"/></inline-formula>, either <inline-formula> <graphic file="1029-242X-2009-486375-i4.gif"/></inline-formula>, or <inline-formula> <graphic file="1029-242X-2009-486375-i5.gif"/></inline-formula>. We show the superstability of the functional equation <inline-formula> <graphic file="1029-242X-2009-486375-i6.gif"/></inline-formula>. More explicitly, if <inline-formula> <graphic file="1029-242X-2009-486375-i7.gif"/></inline-formula> and <inline-formula> <graphic file="1029-242X-2009-486375-i8.gif"/></inline-formula> satisfies <inline-formula> <graphic file="1029-242X-2009-486375-i9.gif"/></inline-formula> for each <inline-formula> <graphic file="1029-242X-2009-486375-i10.gif"/></inline-formula>, then <inline-formula> <graphic file="1029-242X-2009-486375-i11.gif"/></inline-formula> for all <inline-formula> <graphic file="1029-242X-2009-486375-i12.gif"/></inline-formula>, or <inline-formula> <graphic file="1029-242X-2009-486375-i13.gif"/></inline-formula> for all <inline-formula> <graphic file="1029-242X-2009-486375-i14.gif"/></inline-formula>. In the latter case, the constant <inline-formula> <graphic file="1029-242X-2009-486375-i15.gif"/></inline-formula> is the best possible.</p>
ISSN:1025-5834
1029-242X