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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Jafari, M., Darvazebanzade, R. (2023). Approximate symmetry group analysis and similarity reductions of the perturbed mKdV-KS equation. Computational Methods for Differential Equations, 11(1), 175-182. doi: 10.22034/cmde.2022.48341.2022
Mehdi Jafari; Razie Darvazebanzade. "Approximate symmetry group analysis and similarity reductions of the perturbed mKdV-KS equation". Computational Methods for Differential Equations, 11, 1, 2023, 175-182. doi: 10.22034/cmde.2022.48341.2022
Jafari, M., Darvazebanzade, R. (2023). 'Approximate symmetry group analysis and similarity reductions of the perturbed mKdV-KS equation', Computational Methods for Differential Equations, 11(1), pp. 175-182. doi: 10.22034/cmde.2022.48341.2022
Jafari, M., Darvazebanzade, R. Approximate symmetry group analysis and similarity reductions of the perturbed mKdV-KS equation. Computational Methods for Differential Equations, 2023; 11(1): 175-182. doi: 10.22034/cmde.2022.48341.2022