On the superstability of the cosine and sine type functional equations
Annales Universitatis Paedagogicae Cracoviensis. Studia Mathematica, no. 15 (2016)
In this paper, we study the superstablity problem of the cosine and sine type functional equations:f(xσ(y)a)+f(xya)=2f(x)f(y) f(xσ (y)a) + f(xya) = 2f(x)f(y)andf(xσ(y)a)−f(xya)=2f(x)f(y), f(xσ (y)a) - f(xya) = 2f(x)f(y),where f : S → ℂ is a complex valued function; S is a semigroup; σ is an involution of S and a is a fixed element in the center of S.
Keywords:
functional equation, superstablity, stablity
@article{AUPCM_2016_15_a6,
author = {Lehlou, Fouad and Moussa, Mohammed and Roukbi, Ahmed and Kabbaj, Samir},
title = {On the superstability of the cosine and sine type functional equations},
journal = {Annales Universitatis Paedagogicae Cracoviensis. Studia Mathematica},
year = {2016},
number = {15},
language = {en},
url = {http://geodesic.mathdoc.fr/item/AUPCM_2016_15_a6/}
}
TY - JOUR AU - Lehlou, Fouad AU - Moussa, Mohammed AU - Roukbi, Ahmed AU - Kabbaj, Samir TI - On the superstability of the cosine and sine type functional equations JO - Annales Universitatis Paedagogicae Cracoviensis. Studia Mathematica PY - 2016 IS - 15 UR - http://geodesic.mathdoc.fr/item/AUPCM_2016_15_a6/ LA - en ID - AUPCM_2016_15_a6 ER -
%0 Journal Article %A Lehlou, Fouad %A Moussa, Mohammed %A Roukbi, Ahmed %A Kabbaj, Samir %T On the superstability of the cosine and sine type functional equations %J Annales Universitatis Paedagogicae Cracoviensis. Studia Mathematica %D 2016 %N 15 %U http://geodesic.mathdoc.fr/item/AUPCM_2016_15_a6/ %G en %F AUPCM_2016_15_a6
Lehlou, Fouad; Moussa, Mohammed; Roukbi, Ahmed; Kabbaj, Samir. On the superstability of the cosine and sine type functional equations. Annales Universitatis Paedagogicae Cracoviensis. Studia Mathematica, no. 15 (2016). http://geodesic.mathdoc.fr/item/AUPCM_2016_15_a6/