Invariants for Evolution Equations
نویسندگان
چکیده
In the spirit of the recent work of Ibragimov [1] who adopted the infinitesimal method for calculating invariants of families of differential equations using the equivalence groups, we apply the method to evolution type equations of the form ut = f(x, u)uxx + g(x, u, ux). We show that the equivalence Lie algebra admitted by this equation has two functionally independent differential invariants of the second order.
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