## THERMAL SCIENCE

International Scientific Journal

### POLYNOMIAL CHARACTERISTIC METHOD AN EASY APPROACH TO LIE SYMMETRY

**ABSTRACT**

Along the approach to Lie symmetry, it is always needed to solve an over-determined system, which is difficult and complex if not impossible. Here we suggest a new polynomial characteristic method combined with Lie algorithm to complete symmetry classification for a class of perturbed equations. A differential polynomial characteristic set algorithm is proposed to decompose the determining equations into a series of equations easy to be solved.

**KEYWORDS**

PAPER SUBMITTED: 2019-03-02

PAPER REVISED: 2019-10-27

PAPER ACCEPTED: 2019-10-28

PUBLISHED ONLINE: 2020-06-21

**THERMAL SCIENCE** YEAR

**2020**, VOLUME

**24**, ISSUE

**4**, PAGES [2629 - 2635]

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