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arXiv · 2402.02601

Equivalence transformations and conservation laws for a generalized variable-coefficient Gardner equation

Rafael de la Rosa·María Luz Gandarias·María de los Santos Bruzón
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Abstract

In this paper we study the generalized variable-coefficient Gardner equations of the form $u_t + A(t)u^n\,u_x+ C(t)\,u^{2n}u_x + B(t)\,u_{xxx} + Q(t)\,u =0$. This class broadens out many other equations previously considered: Johnpillai and Khalique (2010), Molati and Ramollo (2012) and Vaneeva, Kuriksha and Sophocleous (2015). Equivalence group of the class under consideration has been constructed which permit an exhaustive study and a simple and clear formulation of the results. Some conservation laws are derived for the nonlinearly self-adjoint equations, based on differential substitutions, and by using the direct method of the multipliers.

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Rafael de la Rosa, María Luz Gandarias, María de los Santos Bruzón. 2024-02-04. Equivalence transformations and conservation laws for a generalized variable-coefficient Gardner equation. https://doi.org/10.1016/j.cnsns.2016.04.009

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