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arXiv · 1309.5521

More Jordan type inequalities

D. Aharonov·U. Elias
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Abstract

The function $ \tan(πx / 2) / (πx / 2) $ is expanded into a Laurent series of $ 1 - x^2 $, where the coefficients are given explicitly as combinations of zeta function of even integers. This is used to achieve a sequence of upper and lower bounds which are very precise even at the poles $ x = 1, -1 $. Similar results are obtained for other trigonometric functions with poles.

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D. Aharonov, U. Elias. 2013-09-21. More Jordan type inequalities. https://arxiv.org/abs/1309.5521

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