English

Integral Kannappan-Sine subtraction and addition law on semigroups

General Mathematics 2025-05-01 v1

Abstract

Let SS be a semigroup, μ\mu a discrete measure on SS and σ:SS\sigma:S \longrightarrow S is an involutive automorphism. We determine the complex-valued solutions of the integral Kannappan-Sine subtraction law Sf(xσ(y)t)dμ(t)=f(x)g(y)f(y)g(x),  x,yS,\int_{S}f(x\sigma(y)t)d\mu(t)=f(x)g(y)-f(y)g(x),\; x,y \in S, and the integral Kannappan-Sine addition law Sf(xσ(y)t)dμ(t)=f(x)g(y)+f(y)g(x),  x,yS.\int_{S}f(x\sigma(y)t)d\mu(t)=f(x)g(y)+f(y)g(x),\; x,y \in S. We express the solutions by means of exponentials on S, the solutions of the special sine addition law f(xy)=f(x)χ(y)+f(y)χ(x),f(xy)=f(x)\chi(y)+f(y)\chi(x), x,ySx,y\in S and the solutions of of the special case of the integral Kannappan-Sine addition law Sf(xσ(y)t)dμ(t)=[f(x)χ(y)+f(y)χ(x)]Sχ(t)dμ(t),\int_{S}f(x\sigma(y)t)d\mu(t)=[f(x)\chi(y)+f(y)\chi(x)]\int_{S}\chi(t)d\mu(t), x,ySx,y\in S, and where χ\chi: SCS\longrightarrow \mathbb{C} is an exponential. The continuous solutions on topological semigroups are also given.

Keywords

Cite

@article{arxiv.2504.21057,
  title  = {Integral Kannappan-Sine subtraction and addition law on semigroups},
  author = {Ajebbar Omar and Elqorachi Elhoucien and Jafar Ahmed},
  journal= {arXiv preprint arXiv:2504.21057},
  year   = {2025}
}