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Akanksha Saxena

Publications and source records attributed to Akanksha Saxena.

4 recordsLinked to original sources

Convergence Criteria of a Three Step Scheme under generalized Lipschitz Condition in Banach Spaces

The goal of this study is to investigate the local convergence of a three-step Newton-Traub technique for solving nonlinear equations in Banach spaces with a convergence rate of five. The first order derivative of a nonlinear operator is assumed to satisfy the generalized Lipschitz condition, i.e. the $κ$-average condition. Furthermore, a few results on the convergence of the same method in Banach spaces are developed under the assumption that the derivative of the operators satisfies the radius or center Lipschitz condition with a weak $κ$-average, and that $κ$ is a positive integrable function but not necessarily non-decreasing. Our new notion provides a tighter convergence analysis without the need for new circumstances. As a result, we broaden the applicability of iterative approaches. Theoretical results are supported further by illuminating examples. The existence and uniqueness of the solution $x^*$ are examined in the convergence theorem. In the end, we achieve weaker sufficient convergence criteria and more specific information on the position of the solution than previous efforts requiring the same computational effort. We obtain the convergence theorems as well as some novel results by applying the results to some specific functions for $κ(u)$. A numerical test is carried out to corroborate the hypothesis established in this work.

math.NA

Extended Local Convergence for Seventh order method with $ψ$-continuity condition in Banach Spaces

In this article, the local convergence analysis of the multi-step seventh order method is presented for solving nonlinear equations. The point worth noting in our paper is that our analysis requires a weak hypothesis where the Fréchet derivative of the nonlinear operator satisfies the $ψ$-continuity condition and extends the applicability of the computation when both Lipschitz and Hölder conditions fail. The convergence in this study is shown under the hypotheses on the first order derivative without involving derivatives of the higher-order. To find a subset of the original convergence domain, a strategy is devised. As a result, the new Lipschitz constants are at least as tight as the old ones, allowing for a more precise convergence analysis in the local convergence case. Some numerical examples are provided to show the performance of the method presented in this contribution over some existing schemes.

math.NA

Broadening the convergence domain of Seventh-order method satisfying Lipschitz and Hölder conditions

In this paper, the local convergence analysis of the multi-step seventh order method is presented for solving nonlinear equations assuming that the first-order Fréchet derivative belongs to the Lipschitz class. The significance of our work is that it avoids the standard practice of Taylor expansion thereby, extends the applicability of the scheme by applying the technique based on the first-order derivative only. Also, this study provides radii of balls of convergence, the error bounds in terms of distances in addition to the uniqueness of the solution. Furthermore, generalization of this analysis satisfying Hölder continuity condition is provided since it is more relaxed than Lipschitz continuity condition. We have considered some numerical examples and computed the radii of the convergence balls.

math.NA

On the Local convergence of two-step Newton type Method in Banach Spaces under generalized Lipschitz Conditions

The motive of this paper is to discuss the local convergence of a two-step Newton type method of convergence rate three for solving nonlinear equations in Banach spaces. It is assumed that the first order derivative of nonlinear operator satisfies the generalized Lipschitz i.e. $L$-average condition. Also, some results on convergence of the same method in Banach spaces are established under the assumption that the derivative of the operators satisfies the radius or center Lipschitz condition with a weak $L$-average particularly it is assumed that $L$ is positive integrable function but not necessarily non-decreasing.

math.NA