Convergence Analysis of Newton-Raphson Method for Nonlinear Integral Equations

Abstract

This paper presents a comprehensive convergence analysis of the Newton-Raphson method applied to nonlinear integral equations in Banach spaces. We establish local and global convergence theorems under appropriate conditions on the Fréchet derivative of the integral operator. The analysis demonstrates that the method exhibits quadratic convergence in a neighborhood of the solution when the derivative satisfies a Lipschitz condition. We derive explicit error bounds and convergence rates, providing both theoretical foundations and practical criteria for implementation. Numerical examples illustrate the theoretical results and demonstrate the effectiveness of the method for various classes of nonlinear Fredholm and Volterra integral equations. The results extend classical finite-dimensional convergence theory to infinite-dimensional function spaces and provide a rigorous framework for analyzing iterative solutions of operator equations.