Mathematical Inequalities & Applications · Volume 23, Issue 2 Identities and inequalities for the cosine and sine functions 23-62 Pages 751-757 DOI 10.7153/mia-2020-23-62 Downloads Short PDF Full PDF PNG Authors Iosif Pinelis Keywords inequalities trigonometric functions cosine function sine function Bessel function series expansions approximations Subject classes 26D05 26D15 40A25 41A58