2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/92806A density operator of a bipartite quantum system is called robustly separable if it has a neighborhood of separable operators. Given a bipartite density matrix, its property to be robustly separable is reduced, using the continuous ensemble method, to a finite number of numerical equations. The solution of this system exists for any robustly separable density operator and provides its representation by a continuous mixture of pure product states.12 pages, LaTeXQuantum Physicstext