DOI QR코드

DOI QR Code

VARIANTS OF WILSON'S FUNCTIONAL EQUATION ON SEMIGROUPS

  • Ajebbar, Omar (Department of Mathematics Faculty of Sciences Ibn Zohr University) ;
  • Elqorachi, Elhoucien (Department of Mathematics Faculty of Sciences Ibn Zohr University)
  • Received : 2019.09.16
  • Accepted : 2019.12.26
  • Published : 2020.07.31

Abstract

Given a semigroup S generated by its squares equipped with an involutive automorphism 𝝈 and a multiplicative function 𝜇 : S → ℂ such that 𝜇(x𝜎(x)) = 1 for all x ∈ S, we determine the complex-valued solutions of the following functional equations f(xy) + 𝜇(y)f(𝜎(y)x) = 2f(x)g(y), x, y ∈ S and f(xy) + 𝜇(y)f(𝜎(y)x) = 2f(y)g(x), x, y ∈ S.

Keywords

References

  1. M. R. Abdollahpour, R. Aghayari, and M. Th. Rassias, Hyers-Ulam stability of associated Laguerre differential equations in a subclass of analytic functions, J. Math. Anal. Appl. 437 (2016), no. 1, 605-612. https://doi.org/10.1016/j.jmaa.2016.01.024
  2. J. Aczel, Lectures on functional equations and their applications, translated by Scripta Technica, Inc. Supplemented by the author. Edited by Hansjorg Oser, Mathematics in Science and Engineering, Vol. 19, Academic Press, New York, 1966.
  3. B. Bouikhalene and E. Elqorachi, A class of functional equations of type d'Alembert on monoids, In Anastassiou, G. and Rassias, J.M. (eds.) Frontiers in Functional equations and Analytic Inequalities, pp. 219-235. Springer International Publishing, 2019.
  4. B. Ebanks and H. Stetkaer, d'Alembert's other functional equation on monoids with an involution, Aequationes Math. 89 (2015), no. 1, 187-206. https://doi.org/10.1007/s00010-014-0303-5
  5. B. Ebanks and H. Stetkaer, On Wilson's functional equations, Aequationes Math. 89 (2015), no. 2, 339-354. https://doi.org/10.1007/s00010-014-0287-1
  6. E. Elqorachi and A. Redouani, Solutions and stability of a variant of Wilson's functional equation, Proyecciones 37 (2018), no. 2, 317-344. https://doi.org/10.4067/s0716-09172018000200317
  7. B. Fadli, D. Zeglami, and S. Kabbaj, A variant of Wilson's functional equation, Publ. Math. Debrecen 87 (2015), no. 3-4, 415-427. https://doi.org/10.5486/PMD.2015.7243
  8. S.-M. Jung, Hyers-Ulam-Rassias stability of functional equations in mathematical analysis, Hadronic Press, Inc., Palm Harbor, FL, 2001.
  9. S.-M. Jung, M. Th. Rassias, and C. Mortici, On a functional equation of trigonometric type, Appl. Math. Comput. 252 (2015), 294-303. https://doi.org/10.1016/j.amc.2014.12.019
  10. Pl. Kannappan, Functional equations and inequalities with applications, Springer Monographs in Mathematics, Springer, New York, 2009. https://doi.org/10.1007/978-0-387-89492-8
  11. Y.-H. Lee, S.-M. Jung, and M. Th. Rassias, Uniqueness theorems on functional inequalities concerning cubic-quadratic-additive equation, J. Math. Inequal. 12 (2018), no. 1, 43-61. https://doi.org/10.7153/jmi-2018-12-04
  12. P. K. Sahoo and P. Kannappan, Introduction to Functional Equations, CRC Press, Boca Raton, FL, 2011.
  13. H. Stetkaer, Functional Equations on Groups, World Scientific Publishing Co. Pte. Ltd., Hackensack, NJ, 2013. https://doi.org/10.1142/8830
  14. H. Stetkaer, A variant of d'Alembert's functional equation, Aequationes Math. 89 (2015), no. 3, 657-662. https://doi.org/10.1007/s00010-014-0253-y
  15. H. Stetkaer, More about Wilson's functional equation, Aequationes. Math. (2019), http//doi.org/10.1007/s00010-019-00654-9
  16. W. H. Wilson, On certain related functional equations, Bull. Amer. Math. Soc. 26 (1920), no. 7, 300-312. https://doi.org/10.1090/S0002-9904-1920-03310-0
  17. W. H. Wilson, Two general functional equations, Bull. Amer. Math. Soc. 31 (1925), no. 7, 330-334. https://doi.org/10.1090/S0002-9904-1925-04045-8