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

Taekyun Kim; Dae San Kim

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arXiv · 2407.19885

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

Taekyun Kim·Dae San Kim

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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 {\pi}2, from a series expansion of tan x, which gives the product expansion of the cosine function.

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Taekyun Kim, Dae San Kim. 2024-07-29. Explicit formulas related to Euler's product expansion for cosine function. https://arxiv.org/abs/2407.19885

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