Aksoy, YPakdemirli, M2024-07-182024-07-180898-12211873-7668http://akademikarsiv.cbu.edu.tr:4000/handle/123456789/1807Perturbation-iteration theory is systematically generated for both linear and nonlinear second-order differential equations and applied to Bratu-type equations. Different perturbation-iteration algorithms depending upon the number of Taylor expansion terms are proposed. Using the iteration formulas derived using different perturbation-iteration algorithms, new solutions of Bratu-type equations are obtained. Solutions constructed using different perturbation-iteration algorithms are contrasted with each other as well as with numerical solutions. It is found that algorithms with more Taylor series expansion terms yield more accurate results. (C) 2010 Elsevier Ltd. All rights reserved.EnglishDEGREE-OF-FREEDOMNONLINEAR OSCILLATIONSPERIODIC-SOLUTIONSLIMIT-CYCLEALGORITHMSYSTEMSArticle