We study the convergence of a method of Steffensen-type, which is obtained from the Lagrange polynomial of inverse interpolation with controlled nodes. Conditions are given such that the sequences bilaterally approximate the solution of an equation.
nonlinear equations in R; Steffensen type method; monotone iterations.
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I. Păvăloiu, Bilateral approximations of solutions of equations by order three Steffensen-type methods, Studia Univ. Babeş-Bolyai, Mathematica, vol. 51 (2006) no. 3, pp. 105-114.