Approximate symmetry group analysis and similarity reductions of the perturbed mKdV-KS equation

Document Type : Research Paper


Department of Mathematics, Payame Noor University, PO BOX 19395-4697, Tehran, Iran.


In this paper, we apply the approximate symmetry transformation group to obtain the approximate symmetry group of the perturbed mKdV-KS equation which is a modified Korteweg-de Vries (mKdV) equation with a higher singularity perturbed term as the Kuramoto-Sivashinsky (KS) equation. Also, an optimal system of one-dimensional subalgebras of symmetry algebra is constructed and the corresponding differential invariants and some approximately invariant solutions of the equation are computed. 


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