Asymptotic stepwise solutions of the Korteweg-de Vries equation with a singular perturbation and their accuracy

2021;
: pp. 410–421
https://doi.org/10.23939/mmc2021.03.410
Received: March 05, 2021
Accepted: June 19, 2021

Mathematical Modeling and Computing, Vol. 8, No. 3, pp. 410–421 (2021)

1
Taras Shevchenko National University of Kyiv
2
Taras Shevchenko National University of Kyiv
3
Taras Shevchenko National University of Kyiv
4
Taras Shevchenko National University of Kyiv
5
Borys Grinchenko Kyiv University

The paper deals with the Korteweg-de Vries equation with variable coefficients and a small parameter at the highest derivative.  The asymptotic step-like solution to the equation is obtained by the non-linear WKB technique.  An algorithm of constructing the higher terms of the asymptotic step-like solutions is presented.  The theorem on the accuracy of the higher asymptotic approximations is proven.  The proposed technique is demonstrated by example of the equation with given variable coefficients.  The main term and the first asymptotic approximation of the given example are found, their analysis is done and statement of the approximate solutions accuracy is presented.

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