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arXiv · 2305.05444

A Pexider equation containing the aritmetic mean

Tibor Kiss
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Abstract

In this paper we determine the solutions $(φ,f_1,f_2)$ of the Pexider functional equation \[φ\Big(\frac{x+y}2\Big)\big(f_1(x)-f_2(y)\big)=0,\qquad (x,y)\in I_1\times I_2,\] where $I_1$ and $I_2$ are nonempty open subintervals. Special cases of the above equation regularly arise in problems with two-variable means. We show that, under a rather weak regularity condition, the coordinate-functions of a typical solution of the equation are constant over several subintervals of their domain. The regularity condition in question will be that the set of zeros of $φ$ is closed. We also discuss particular solutions where this condition is not met.

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Tibor Kiss. 2023-05-09. A Pexider equation containing the aritmetic mean. https://arxiv.org/abs/2305.05444

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