2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/94621We present a simple and effective method for constructing exactly solvable cosmological models containing inflation with exit. This method does not involve any parameter fitting. We discuss the problems arising with solutions that violate the weak energy condition.10 pages, 6 figures, RevTexHigh Energy Physics - TheoryThe Darboux Transformation and Exactly Solvable Cosmological Modelstext