A Kannappan-Cosine Functional Equation on Semigroups

Jafar, Ahmed; Ajebbar, Omar; Elqorachi, Elhoucien

doi:10.2478/amsil-2024-0012

Abstract

In this paper we determine the complex-valued solutions of the Kannappan-cosine functional equation g(xyz₀) = g(x)g(y) − f (x)f (y), x, y ∈ S, where S is a semigroup and z₀ is a fixed element in S.

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A Kannappan-Cosine Functional Equation on Semigroups

Abstract

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