Conditional Equations Related to Drygas Functional Equations

Sadegh Izadi; Sedigheh Jahedi; Mehdi Dehghanian

doi:10.2478/amsil-2025-0015

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Conditional Equations Related to Drygas Functional Equations

Annales Mathematicae Silesianae

Volume 40 (2026): Issue 1 (March 2026)

By: Sadegh Izadi , Sedigheh Jahedi and Mehdi Dehghanian

Open Access

|Oct 2025

Abstract

We determine the solutions of the conditional Drygas equation for functions f₁ and f₂ that satisfy (y² + y)f₁(x) = (x² + x)f₂(y) for all (x, y) ∈ ℝ² under the additional conditions y = x², or y = log(x), x > 0 or y = exp(x).

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Articles in this issue

DOI: https://doi.org/10.2478/amsil-2025-0015 | Journal eISSN: 2391-4238 | Journal ISSN: 0860-2107

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Language: English

Page range: 98 - 111

Submitted on: Aug 5, 2024

Accepted on: Sep 23, 2025

Published on: Oct 31, 2025

Published by: University of Silesia in Katowice, Institute of Mathematics

In partnership with: Paradigm Publishing Services

Publication frequency: 2 issues per year

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© 2025 Sadegh Izadi, Sedigheh Jahedi, Mehdi Dehghanian, published by University of Silesia in Katowice, Institute of Mathematics
This work is licensed under the Creative Commons Attribution 4.0 License.

Volume 40 (2026): Issue 1 (March 2026)