Conditional symmetry and reduction of differential equations with partial derivatives

W. I. Fushchich; R. Z. Zhdanov

W. I. Fushchich Inst. Math. Acad. Sci. Ukraine, Kiev
R. Z. Zhdanov Inst. Math. Acad. Sci. Ukraine, Kiev

Keywords: -

Abstract

We establish sufficient conditions of reduction of partial differential equations admitting nontrivial conditional symmetry. The results obtained generalize the classical conditions of reduction of differential equations by using group-invariant solutions. Some examples of reduction of systems of partial differential equations both by number of independent and dependent variables are considered.

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