A Kannappan-Cosine Functional Equation on Semigroups
Ahmed Jafar, Omar Ajebbar, Elhoucien Elqorachi
Solutions and Stability of Generalized Kannappan’s and Van Vleck’s Functional Equations
Elhoucien Elqorachi, Ahmed Redouani
Cosine and Sine Addition and Subtraction Law with an Automorphism
Youssef Aserrar, Elhoucien Elqorachi
On the Alienation of Multiplicative and Additive Functions
Mohamed Chakiri, Abdellatif Chahbi, Elhoucien Elqorachi