D. Zeglami

On the Superstability of Trigonometric Type Functional Equations

D. Zeglami & S. Kabbaj · Journal of Advances in Mathematics and Computer Science · 2014

The aim of this paper is to study the superstability for the mixed trigonometric functional equation:                                                            and the stability of the Pexider type functional equation:                          where  G is any group, not necessar...

Open access Research Article 10.9734/BJMCS/2014/7792

On the Superstability of a Generalization of the Cosine Equation

D. Zeglami, S. Kabbaj & A. Roukbi · Journal of Advances in Mathematics and Computer Science · 2013

The aim of this paper is to investigate the stability problem for the functional equation:                                       ƒ(xy)+ƒ(xσ(y))=2g(x)ƒ(y),      x,y∈G                      (Eg,ƒ) and the superstability of the d'Alembert's equation:                                  ...

Open access Research Article 10.9734/BJMCS/2014/6548