Abstract
The function tan(πx/2)/(πx/2) is expanded into a Laurent series of 1 - x2, 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 at x = ±1. Similar results are obtained for other trigonometric functions with poles.
Original language | English |
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Pages (from-to) | 1563-1577 |
Number of pages | 15 |
Journal | Mathematical Inequalities and Applications |
Volume | 17 |
Issue number | 4 |
DOIs | |
State | Published - 1 Oct 2014 |
Keywords
- Dirichlet functions
- Jordan inequality
- Laurent series
- Trigonometric inequalities
- Zeta function
ASJC Scopus subject areas
- General Mathematics
- Applied Mathematics