Lie symmetries of differential equations by computer algebra (Q1275788)

A three dimensional solvable algebra of classical symmetries of the equation \(u_{tt}=a\dot u_{xx}+b\dot u_{xxxx}+c(u^2)_{xx}\) is calculated with the help of computer the algebraic system Mathematica and package Lie [\ ] from the preprint: [\textit{G. Baumann}, Lie symmetries of differential equations. A Mathematica program to determine Lie symmetries, Preprint (1996)]. The obtained symmetries are used to obtain reductions of this equation to ordinary differential equations.