APMAdvances in Pure Mathematics2160-0368Scientific Research Publishing10.4236/apm.2014.47043APM-48244ArticlesPHYSICS & MATHEMATICSReply to Comment on “On Humbert Matrix Polynomials of Two Variables”GhaziS. Khammash1AymanShehata2Department of Mathematics, Al-Aqsa University, Gaza Strip, PalestineDepartment of Mathematics, Faculty of Science, Assiut University, Assiut, Egypt0707201404073243255 May 201425 June 2014 2 July 2014© Copyright 2014 by authors and Scientific Research Publishing Inc. 2014This work is licensed under the Creative Commons Attribution International License (CC BY). http://creativecommons.org/licenses/by/4.0/

The formula subject to comment in Reference  is correct.

Matrix Functions Humbert Matrix Polynomials
1. Introduction and Motivation

This reply is written as an answer to the paper   .

In the comment  , the author points out that the generating matrix function given in Formula (7) in our recently published paper 

is not true, because the domain is not clarified. And the author notes, that

for that it can be zero, and then it is meaningless. Further he writes: “For this, first we have to observe that for matrix, we define where is the exponential matrix. Of course, has sense only for”. To clarify the situation, let us write down the relation for any matrix in the following relation

holds  (see also   ). From above we maintain that, from above and from (1) we conclude our reply by noting that the relation ( Humbert matrix polynomials of two variables (7)  ) is generated by

where is positive integer.

In paper  the author notes that in “Remark” comments that the double generating Formula (8) 

is not true. We conclude our reply by noting that we consider our relation (8) with the help of (1) provided that

and not equal 1. Note that, in a variety of different research papers our own paper it

has been written with approximate resemblance with other papers in the methods, for example, Dattoli et al.  and Pathan and Khan  . In conclusion, we accept blame for not clarifying the domain because this perhaps causes misunderstanding for readers who are not totally familiar with literature in this area. However, note that even accepting Soler interpretation, from (1) which is written in   and it is not mentioned in Soler comments   , the conjecture counter examples remain false in   . However, our results are original and correct.

AMS 2010 Subject Classification

Primary 33C45, 15A15. Secondary 33C45, 15A60

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