2023/10/24 by T. M. Dunster, Dunster, T. M. · 4 citations
Mathematics · #33C10 #34E05 #34E20 #Classical Analysis and ODEs (math.CA) #FOS: Mathematics #Iterative Methods for Nonlinear Equations #Mathematical functions and polynomials #Numerical methods in inverse problems
paper · pdf · doi:10.48550/arxiv.2310.16016
openalex publication_date 2023/10/24 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
Reformulated uniform asymptotic expansions are derived for ordinary differential equations having a large parameter and a simple turning point. These involve Airy functions, but not their derivatives, unlike traditional asymptotic expansions. From these, asymptotic expansions are derived for the zeros of Bessel functions that are valid for large positive values of the order, uniformly valid for all the zeros. The coefficients in the expansions are explicitly given elementary functions, and similar expansions are derived for the zeros of the derivatives of Bessel functions.