relation: https://khub.utp.edu.my/scholars/11301/ title: Optimal fourth- and eighth-order of convergence derivative-free modifications of King's method creator: Said Solaiman, O. creator: Abdul Karim, S.A. creator: Hashim, I. description: Starting by King's method, we propose a modified families of fourth- and eighth-order of convergence iterative methods for nonlinear equations. The fourth-order method requires at each iteration three function evaluations, while the eighth-order methods both need four function evaluations. The proposed methods are derivative-free. Based on the conjecture of Kung and Traub, the new methods attain the optimality with efficiency index 1.587 for the fourth-order method and 1.68 for the eighth-order methods. The convergence analyses of the methods are given, and comparisons with some well-known schemes having identical order of convergence demonstrate the efficiency of the present techniques. © 2018 The Authors publisher: Elsevier B.V. date: 2019 type: Article type: PeerReviewed identifier: Said Solaiman, O. and Abdul Karim, S.A. and Hashim, I. (2019) Optimal fourth- and eighth-order of convergence derivative-free modifications of King's method. Journal of King Saud University - Science, 31 (4). pp. 1499-1504. ISSN 10183647 relation: https://www.scopus.com/inward/record.uri?eid=2-s2.0-85057957375&doi=10.1016%2fj.jksus.2018.12.001&partnerID=40&md5=a70f1e060da4974c0d21debf73e325a0 relation: 10.1016/j.jksus.2018.12.001 identifier: 10.1016/j.jksus.2018.12.001