2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/222789In this paper we give a geometric interpretation of a reduction method based on the so called $λ$-variational symmetry (C. Muriel, J.L. Romero and P. Olver 2006 \emph{Variational $C^{\infty}$-symmetries and Euler-Lagrange equations} J. Differential equations \textbf{222} 164-184). In general this allows only a partial reduction but it is particularly suitable for the reduction of variational ODEs with a lack of computable local symmetries. We show that this method is better understood as a nonlocal symmetry-reduction.Dynamical SystemsMathematical Physics37K05; 34C14; 70S10text