2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/128001We prove an implicit function theorem for C^k-maps from arbitrary topological vector spaces over valued fields to Banach spaces (for k at least 2). As a tool, we show the C^k-dependence of fixed points on parameters for suitable families of contractions of a Banach space. Similar results are obtained for k times strictly differentiable maps, and for k times Lipschitz differentiable maps. In the real case, our results subsume an implicit function theorem for Keller C^k_c-maps from arbitrary topological vector spaces to Banach spaces.LaTeX, 59 pages, broadly written preprint (v2: new Appendix C extends C^1-case from locally compact fields to complete valued fields)Functional AnalysisGeneral Mathematics58C15; 47H10; 26E30; 58C20; 46S10; 26E15; 26E20text