Geodesic
About cotangent
Čebyševskij sbornik, Tome 24 (2023) no. 5, pp. 167-179.

Voir la notice de l'article provenant de la source Math-Net.Ru

In this paper we describe a reasoning method which allows to get relatively simple estimates of cotangent values for angles in the half-interval $(0, \pi/2 ]$. The method is based on the ability of the cotangent to refine some of its estimates that were derived from other considerations. As an illustration of the method we give cotangent estimates for two subclasses of rational functions.
Keywords: cotangent, estimations, minorants, majorants. 
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S. Yu. Soloviev. About cotangent. Čebyševskij sbornik, Tome 24 (2023) no. 5, pp. 167-179. http://geodesic.mathdoc.fr/item/CHEB_2023_24_5_a10/

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