Explicit formulas related to Euler's product expansion for cosine function

2024/07/29 by Taekyun Kim, Kim, Taekyun, Dae San Kim +1
Mathematics · #Functional Equations Stability Results #Mathematical functions and polynomials #Iterative Methods for Nonlinear Equations

paper · pdf · doi:10.48550/arxiv.2407.19885

Abstract

In this paper, we derive by using elementary methods some continued fractions, certain identities involving derivatives of tanx, several expressions for log coshx and an identity for π2, from a series expansion of tan x, which gives the product expansion of the cosine function.

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