A new generalized and sharp version of Jordan’s inequality and its applications to the improvement of the Yang Le inequality. (English) Zbl 1132.26334

Wu, Shanhe; Debnath, Lokenath

Appl. Math. Lett. 19, No. 12, 1378-1384 (2006).

Summary: A new generalized and sharp version of Jordan’s inequality is proved and it is applied in the improvement of the Yang Le inequality. Moreover, a mistake in the proof of sharpening Jordan’s inequality due to Zhu [S.H. Wu, On generalizations and refinements of Jordan type inequality, Octogon Math. Mag. 12, No. 1, 267–272 (2004)] is corrected.

MSC:

26D05

Inequalities for trigonometric functions and polynomials

Keywords:

Jordan’s inequality; Yang Le inequality; sharpness; generalization; best constant

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