SOME GENERAL WILKER-HUYGENS INEQUALITIES.

In this paper, we provide a systematic way to study on some general Wilker-Huygens type inequalities for the trigonometric and hyperbolic functions, lemniscate and hyperbolic lemniscate functions, and their corresponding inverse functions. Our results are some extensions and refinements of the recently published results in [A. Mhanna, On a general Huygens-Wilker inequality, Appl. Math. E.-Notes, 20 (2020), 79-81; MR4076436], and improve many previous results involving Wilker-Huygens type inequalities. [ABSTRACT FROM AUTHOR]