On the general and measurable solutions of some functional equations



Abstract

The general solutions of two functional equations, without imposing any regularity condition on any of the functions appearing, have been obtained. From these general solutions, the Lebesgue measurable solutions have been deduced by assuming the function(s) to be measurable in the Lebesgue sense.


Keywords

logarithmic function; multiplicative function; function measurable in the Lebesgue sense; continuous function; stability of a functional equation; the Shannon entropy

1. Behara M., Additive and Nonadditive Measures of Entropy, Wiley Eastern Limited, New Delhi–Bombay, 1990.
2. Chaundy T.W., Mcleod J.B., On a functional equation, Edinburgh Math. Notes. 43 (1960), 7–8.
3. Kannappan PL., Sahoo P.K., On a functional equation connected to sum form nonadditive information measures on an open domain-II, Glas. Mat. 22(42) (1987), 343–351.
4. Kocsis I., Maksa Gy., The stability of a sum form functional equation arising in information theory, Acta Math. Hungar. 79 (1998), no. 1–2, 39–48.
5. Losonczi L., Sum form equations on open domain, Utilitas Math. 29 (1986), 125–132.
6. Losonczi L., Maksa Gy., The general solution of a functional equation in information theory, Glas. Mat. 16(36) (1981), 261–266.
7. Maksa Gy., Páles Z., Hyperstability of a class of linear functional equations, Acta Math. Paed. Nyire 17 (2001), 107–112.
8. Nath P., On a functional equation and its relevance in information theory, in: Advances in Information Theory and Operations Research, Om Parkash (Ed.), VDM Verlag, Saarbrucken, Germany, 2010, pp. 1–14.
9. Nath P., Singh D.K., On a sum form functional equation related to entropies and some moments of a discrete random variable, Demonstratio Math. 42 (2009), no. 1, 83–96.
10. Shannon C.E., A mathematical theory of communication, Bell. Syst. Tech. Jour. 27 (1948), 348–423; 623–656.
11. Tabor J., Stability of the Cauchy equation with variable bound, Publ. Math. Debrecen 51 (1997), 165–173.
Download

Published : 2017-08-05


NathP., & SinghD. K. (2017). On the general and measurable solutions of some functional equations. Annales Mathematicae Silesianae, 32, 285-294. Retrieved from https://journals.us.edu.pl/index.php/AMSIL/article/view/13927

Prem Nath 
Department of Mathematics, University of Delhi, India  India
Dhiraj Kumar Singh  dhiraj426@rediffmail.com
Department of Mathematics, Zakir Husain Delhi College (University of Delhi), India  India



The Copyright Holders of the submitted text are the Author and the Journal. The Reader is granted the right to use the pdf documents under the provisions of the Creative Commons 4.0 International License: Attribution (CC BY). The user can copy and redistribute the material in any medium or format and remix, transform, and build upon the material for any purpose.

  1. License
    This journal provides immediate open access to its content under the Creative Commons BY 4.0 license (http://creativecommons.org/licenses/by/4.0/). Authors who publish with this journal retain all copyrights and agree to the terms of the above-mentioned CC BY 4.0 license.
  2. Author’s Warranties
    The author warrants that the article is original, written by stated author/s, has not been published before, contains no unlawful statements, does not infringe the rights of others, is subject to copyright that is vested exclusively in the author and free of any third party rights, and that any necessary written permissions to quote from other sources have been obtained by the author/s.
  3. User Rights
    Under the Creative Commons Attribution license, the users are free to share (copy, distribute and transmit the contribution) and adapt (remix, transform, and build upon the material) the article for any purpose, provided they attribute the contribution in the manner specified by the author or licensor.
  4. Co-Authorship
    If the article was prepared jointly with other authors, the signatory of this form warrants that he/she has been authorized by all co-authors to sign this agreement on their behalf, and agrees to inform his/her co-authors of the terms of this agreement.