Abstract
The existence of sine and cosine series as a Fourier series, their \(L^1\)-convergence seems to be one of the prominent question in theory of convergence of trigonometric series in \(L^1\)-metric norm. In the literature, till now most of the authors have studied the \(L^1\)-convergence of cosine trigonometric series. However, very few of them have studied the \(L^1\)-convergence of trigonometric sine series. In this paper, new modified cosine and sine sums of Fourier series are introduced and a criterion for the summability and \(L^1\)-convergence of these modified sums is obtained. Also, necessary and sufficient condition for the \(L^1\)-convergence of cosine and sine series is deduced as corollaries. Further an application is given to illustrate the main result.
Similar content being viewed by others
References
Rees CS, Stanojevic CV (1973) Necessary and sufficient condition for integrability of certain cosine sums. J Math Anal Appl 43:579–586
Kumari S, Ram B (1988) \(L^1\)-convergence modified cosine sum. Indian J Pure Appl Math 19(11):1101–1104
Ram B, Kumari S (1989) On \(L^1\)-convergence of certain trigonometric sums. Indian J Pure Appl Math 20(9):908–914
Kaur K, Bhatia SS, Ram B (2004) Integrability and \(L^1\)-convergence of modified sine sums. Georgian Math J 11(1):99–104
Kaur J, Bhatia SS (2008) Convergence of new modified Trigonometric sums in the metric space L. J Non Linear Sci Appl 1(3):179–188
Kaur J, Bhatia SS (2012) A class of \(L^1\)-convergence of new modified cosine sum. Southeast Asian Bull Math 36:831–836
Braha NL, Krasniqi XhZ (2009) On \(L^1\)-convergence of certain cosine sums. Bull Math Anal Appl 1(1):55–61
Bary NK (1964) A treatise on trigonometris series, Vol I and Vol II. Pergamon Press, London
Zygmund A (1959) Trigonometric series. University Press, Cambridge
Kano T (1968) Coefficients of some trigonometric series. J Fac Sci Shinshu Univ 3:153–162
Kaur K, Bhatia SS, Ram B (2002) Integrability and \(L^1\)-convergence of Rees–Stanojevic sums with generalized semi-convex coefficients. Int J Math Math Sci 30(11):645–650
Kolmogorov AN (1923) Sur l’ordere de grandeur des coefficients de la series de Fourier–Lebesgue. Bull Acad Pol Sci Ser Sci Math Astronom Phys 83–86
Bala R, Ram B (1987) Trigonometric series with semi-convex coefficients. Tamang J Math 18(1):75–84
Garrett JW, Stanojevic CV (1976) On \(L^1\)-convergence of certain cosine sums. Proc Am Math Soc 54:101–105
Ram B (1977) Convergence of certain cosine sums in the metric \(L\). Proc Am Math Soc 66:258–260
Singh N, Sharma KM (1978) Convergence of certain cosine sums in the metric space \(L\). Proc Am Math Soc 75:117–120
Shuyun S (1990) The entension of the theorems of C.V. Stanojevic and V.B Stanojevic. Proc Am Math Soc 110:895–904
Bosanquet LS (1949) Note on convergence and summability factor III. Proc Lond Math Soc 50:482–496
Author information
Authors and Affiliations
Corresponding author
Additional information
This work is the part of UGC sponsored Major Research Project entitled “On \(L^1\)-convergence of trigonometric series with special coefficients”.
Rights and permissions
About this article
Cite this article
Chouhan, S.K., Kaur, J. & Bhatia, S.S. Convergence and Summability of Fourier Sine and Cosine Series with Its Applications. Proc. Natl. Acad. Sci., India, Sect. A Phys. Sci. 89, 141–148 (2019). https://doi.org/10.1007/s40010-017-0471-5
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s40010-017-0471-5