A Generalized Finite Hankel Type Transformation and a Parseval Type Equation

Transcription

1 International Journal of Scientific and Innovative Mathematical Research (IJSIMR) Volume 4, Issue 1, January 2016, PP ISSN X (Print) & ISSN (Online) wwwarcjournalsorg A Generalized Finite Hankel Type Transformation and a Parseval Type Equation BBWaphare Department of Mathematics, MITACSC, Alandi, Savitribai Phule Pune University,Pune,India balasahebwaphare@gmailcom Abstract: In this paper, we study the finite Hankel type transformation on spaces of generalized functions by developing new procedure Two Hankel type integral transformations and are considered and they satisfy Parseval type equation defined by (12) We have defined a space of functions and a space of complex sequences and it is further shown that and are isomorphisms from onto and onto respectively Finally some applications of new generalized finite Hankel type transformation are established Keywords: Finite Hankel type transformation, Parseval type equation, generalized finite Hankel type transformation 2000 Mathematics subject classification: 46 F 12 1 INTRODUCTION IN Sneddon [14] was first to introduce finite Hankel transforms of classical functions The same was later studied by [3], [4], [7], [15] Recently Zemanian [18], Pandey and Pathak [11] and Pathak [12] extended these transforms to certain spaces of distributions as a special case of general theory on orthonromal series expansions of generalized functions Dube [5], Pathak and Singh [13] and Mendez and Negrin [10] investigated finite Hankel transformations in other spaces of distributions through a procedure quite different from that one which was developed in [18] and [12] We define finite Hankel type transformation of the first kind by for where denotes the Bessel function of the first kind and order and, [17, p596] represent the positive roots of arranged in ascending order of magnitude For and we introduce the space of finitely differentiable functions on (0,1) such that where is equipped with the topology generated by the family of seminorms is a Frechet space denotes the dual of and is endowed with the weak topology For the generalized finite Hankel type transform of is defined by (11) Thus ARC Page 21

2 BBWaphare Our main objective in this paper is to define the finite Hankel type transformation of generalized functions by developing a new procedure We introduce the finite Hankel type transformation by on new spaces when The transformation and are closely connected and they satisfy the Parseval equation (12) when and and are suitable functions We define a space of functions and a space of sequences and we prove that is an isomorphism from onto provided that The generalized finite Hankel type transformation of the dual of is defined through (13) One can notice that (13) appears as a generalization of the Parseval equation (12) We show that the conventional finite Hankel type transformation and generalized finite Hankel type transformation given by (11) are special cases of our generalized transformation Throughout this paper denotes a real number greater or equal to Now require some properties of Bessel functions The behaviours of near the origin and the infinity are the following ones: (14) as (15) where is understood as in Watson [17, p198] The main differentiation formulae for are (16) (17) for where By combining (16) and (17), it can be easily inferred (18) 2 THE SPACES AND THE FINITE HANKEL TYPE TRANSFORMATION Definition 21: We define the as the space of all complex valued functions on such that is infinitely differentiable and satisfies International Journal of Scientific and Innovative Mathematical Research (IJSIMR) Page 22

3 A Generalized Finite Hankel Type Transformation and a Parseval Type Equation (i) (ii) and (iii) where is endowed with the topology generated by the family of seminorms Notice that is a norm for is a Hausdorff topological linear space that verifies the first countability axiom Moreover, the operator defines a continuous mapping from into itself is the dual space of and it is equipped with the usual weak topology We require the following result which will be useful in the sequel Lemma 22: If is a function defined on (0,1) such that is bounded on (0,1), then generates a member of through the definition Proof: The result easily follows from the following inequality Lemma 23: Let and Then and the topology of is stronger than that induced on it by Proof: Let In view of the conditions (i) and (ii) of Definition 21, we can write Therefore Hence, and and is contained in and the inclusion is continuous Thus proof is completed Remark: From Lemma 23, we can deduce that if then the restriction of to is a member of International Journal of Scientific and Innovative Mathematical Research (IJSIMR) Page 23

4 BBWaphare Definition 24: We define as the space of all complex sequences such that where represent the positive roots of the equation arranged in ascending order of magnitude The topology of is that generated by the family of norms where Notice that Thus is Hausdorff topological linear space that satisfies the first countability axiom denotes the dual space of and it is endowed with the weak topology Now we introduce continuous operations in and in the following Lemma Lemma 25: Let be a complex sequence such that and for some and Then the linear operator is a continuous mapping from Moreover the operator in into itself where is a continuous mapping from Proof: It is enough to see that into itself for and where being a suitable positive constant This completes the proof Lemma 26: If is a complex sequence satisfying the same conditions as in Lemma 25, then generates a member of by Now we state our main theorem of this section Theorem 27: For the finite Hankel type transformation is an isomorphism from onto Proof: Let As it is known,, where In view of the operational rule (16), we can write International Journal of Scientific and Innovative Mathematical Research (IJSIMR) Page 24

5 A Generalized Finite Hankel Type Transformation and a Parseval Type Equation However, by (14), since and Hence (21) Now, by invoking (17), we have The limit terms are equal to zero by (14) because Therefore (22) Using relations (21) and (22), we obtain By induction, we have (23) From (23), according to Riemann-Lebesgue Lemma ([17, p 457]), we have Moreover by (15), there exists a positive constant such that and then Now, for certain International Journal of Scientific and Innovative Mathematical Research (IJSIMR) Page 25

6 BBWaphare Since we get and and for some This inequality proves that the linear mapping is continuous from into Now let and define By (14) and (15), we have for a suitable Thus In a similar way we can prove that Moreover by invoking (18) we obtain and Then We can also infer for each and from (14), (15) and (16), for Here and are suitable positive constants Hence On the other hand, as the series defining is uniformly convergent in there exists a positive constant such that Therefore is a continuous mapping from into Finally from Watson [17,p59], we can infer that This completes the proof International Journal of Scientific and Innovative Mathematical Research (IJSIMR) Page 26

7 A Generalized Finite Hankel Type Transformation and a Parseval Type Equation 3 THE GENERALIZED FINITE HANKEL TYPE TRANSFORMATION We define the generalized finite Hankel type transformation as follows (31) Notice that (31) appears as a generalization of the Parseval equation (12) From Zemanian [19, Theorem 110-2] and Theorem 27, we immediately obtain Theorem 31: For the generalized finite Hankel type transformation is an isomorphism from onto In the following theorem, we establish that the conventional finite Hankel type transformation a special case of the generalized finite Hankel type transformation defined in (31) Theorem 32: Let be a function defined on (0,1) such that is bounded on (0,1) Then agrees with as members of is Proof: The conventional finite Hankel type transformation of is defined by Then as is bounded on (0,1) and by (14) and (15) we can write where and are certain positive constants Therefore in view of Lemma 26, generates a member of by The last equality is justified since the series is uniformly convergent on (0,1) and is bounded on (0,1) We can also write International Journal of Scientific and Innovative Mathematical Research (IJSIMR) Page 27

8 BBWaphare Hence according Lemma 22, we conclude as members of Thus proof is completed and We now prove that the generalized finite Hankel type transform of given by (11) is equal (in the sense of equality in ) to the generalized finite Hankel type transform of as given by (31) Theorem 33: Let Then =,, where, Proof: By Zemanian [19, Theorem 18-1], since, there exist and such that Hence, by (14), (15) and (18), we can infer that (32) for a certain By invoking Lemma 26, (32) proves that generates a member of through To prove our assertion, we must establish that Let As it is easy to see, By using (32), we can obtain (33) (34) with Then Moreover, and we obtain (35) International Journal of Scientific and Innovative Mathematical Research (IJSIMR) Page 28

9 A Generalized Finite Hankel Type Transformation and a Parseval Type Equation for a suitable Hence, and because Therefore, since (36) Now from (33), we can conclude and the proof is complete 4 APPLICATION Firstly we prove an operational-transform formula for the generalized finite Hankel type transformation that will be useful in applications Lemma 41: Let be a polynomial and be in Then Proof: If, we have = =, = We consider the functional equation where is a given member of is a polynomial such that and is unknown generalized function but required to be in By applying the generalized finite Hankel type transform to (41) and according to Lemma 41, we can prove that (41) is equivalent to (41) International Journal of Scientific and Innovative Mathematical Research (IJSIMR) Page 29

10 BBWaphare Hence it is not difficult to see that the functional defined by is in and it is the solution for (41) This completes the proof 5 CONCLUSION This paper provides the study of the finite Hankel type transformation on spaces of generalized functions The integral transformations and satisfy Parseval type equation defined above in this paper We have shown that and are isomorphisms from onto and onto respectively Applications of new generalized finite Hankel type transformation established in this paper may be useful in engineering ACKNOWLEDGEMENT Author is thankful to referee for his valuable suggestions in improving this paper REFERENCES [1] Betancor JJ, The Hankel-Schwartz transform for functions of compact support, Rend Mat Appl 7(3-4) (1987), [2] Betancor JJ, A mixed Parseval equation and a generalized Hankel transformation of distributions, Can J Math XLI (2) (1989), [3] Churchill RV, Fourier Series and Boundary Value Problems, Mc Graw-Hill, New York, 1953 [4] Cinelli, A extension of the finite Hankel transform and applications, Inst J Engng 3 (1965), [5] Dube LS, On finite Hankel-transformation of generalized functions, Pacific, J Math 62 (1976), [6] Gelfand IM, Shilov GE, Generalized functions, Vol III Academic Press, New York, 1967 [7] Liu SH, Method of generalized finite Hankel transform, Z Angew Math Mech 51 (1971), [8] Mendez JM, A mixed Parseval equation and the generalized Hankel transformation, Proc Amer Math Soc 102 (1988), [9] Mendez JM, The finite Hankel-Schwartz transform, J Korean Math Soc 26(1) (1989), [10] Mendez JM and Negrin JR, Fourier Bessel Series expansion of generalized functions and finite Hankel transforms of distributions, Rev Roum de Math Pures et Appl XXXIV (7) (1989), [11] Pandey JN, Pathak RS, Eigen function expansion of generalized functions, Nagoya Math J72 (1978), 1-25 [12] Pathak RS, Orthogonal series representations for generalized functions, J Math Anal Appl 130 (1988), [13] Pathak RS, Singh OP, Finite Hankel transforms of distributions, Pacific J Math 99 (1982), [14] Sneddon IN, On finite Hankel transforms, Phil Mag (7) 17 (1946), [15] Sneddon IN, The Use of Integral Transforms, Tata Mc Graw Hill, New Delhi, 1979 [16] Titchmarsh EC, A class of expansions in series of Bessel functions, Proc London Math Soc (2) 22 (1924), Xiii-Xvi [17] Watson GN, Theory of Bessel Functions, 2nded, Cambridge University Press, Cambridge, 1958 [18] Zemanian A H, Orthonormal series expansions of certain distributions and distributional transform calculus, J Math Anal Appl 14(1966), [19] Zemanian A H, Generalized Integral Transformations, Interscience Publishers, New York, 1968 International Journal of Scientific and Innovative Mathematical Research (IJSIMR) Page 30

11 A Generalized Finite Hankel Type Transformation and a Parseval Type Equation AUTHOR S BIOGRAPHY Prof DrBalasaheb Bhagaji Waphare, is a science graduate from Fergusson college, Pune in 1989He has completed his Master and Doctorate degrees from a well known and reputed Savitribai Phule Pune University (Formerly known as University of Pune)Presently he is working as a principal at MAEER Pune s MIT Arts, Commerce & Science College (MITACSC),Alandi(D)He has wide experience of more than 22 years in teaching and research He is a research guide in Mathematics recognized by Savitrivbai Phule Pune University for MPhil and PhD programmes DrBalasaheb Waphare is a very devoted, dedicated and passionate teacher served with distinction He has 10 awards to his name and attended 25 National and International conferences He is also a life member of 08 reputed professional bodies and reviewer of few reputed journalsdrbalasaheb BWaphare has more than 90 research publications to his credits in various reputed National and International journals International Journal of Scientific and Innovative Mathematical Research (IJSIMR) Page 31