Asif, Naseer AhmadTalib, ImranTunc, Cemil2025-05-102025-05-1020151687-277010.1186/s13661-015-0397-22-s2.0-84938692471https://doi.org/10.1186/s13661-015-0397-2https://hdl.handle.net/20.500.14720/7707Tunc, Cemil/0000-0003-2909-8753In this article, the existence of solution for the first-order nonlinear coupled system of ordinary differential equations with nonlinear coupled boundary condition (CBC for short) is studied using a coupled lower and upper solution approach. Our method for a nonlinear coupled system with nonlinear CBC is new and it unifies the treatment of many different first-order problems. Examples are included to ensure the validity of the results.eninfo:eu-repo/semantics/openAccessLower And Upper SolutionsCoupled Nonlinear SystemCoupled Nonlinear Boundary ConditionArzela-Ascoli TheoremSchauder TheoremArticleQ1Q2WOS:000359252000001