Two-dimensional generalized instantaneous images and approximations of the Pade type function of two variables


  • I. S. Teteruk Institute of Mathematics of NASU, Kyiv



Generalized instantaneous image were introduced by V.K. Dzyaduk [1] in 1981 and proved to be a convenient tool for constructing and studying the Padé approximants and their generalizations (see [2]). The method of generalized instantaneous images proposed by Dzyadyk made it possible to construct and study rational Padé approximants and their generalizations for many classes of special functions from a single position. As an example, the Padé approximants is constructed for a class of basic hypergeometric series, which includes a q-analogue of the exponential function. In this paper the construction of the Pade approximants for the function of two variables is investigated. A two-dimensional functional sequence is constructed, which has a generalized instantaneous image, and rational approximants are determined, which will be generalizations of one-dimensional Padé approximants. The function of the two variables is entirely related to the basic hypergeometric series.

Key words: Pade approximation, instantaneous image, hypergeometric series, rational approximation.

Pages of the article in the issue: 75 - 80

Language of the article: Ukrainian


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How to Cite

Teteruk, I. S. (2020). Two-dimensional generalized instantaneous images and approximations of the Pade type function of two variables. Bulletin of Taras Shevchenko National University of Kyiv. Physical and Mathematical Sciences, (1-2), 75–80.



Differential equations, mathematical physics and mechanics