A solution to an open problem for Wilker-type inequalities. (English) Zbl 1468.26009
Summary: This paper is intended to solve the open problem for the Wilker-Type inequality: what are the best possible values for the constants \(c_1\) and \(c_2\) such that the double inequality \(c_qx^{3a}\tan x<(\frac{\sin x}{x})^{2a}+(\frac{\tan x}{x})^a-2<c_2x^{3a}\tan x\) holds?
MSC:
| 26D05 | Inequalities for trigonometric functions and polynomials |
| 33B10 | Exponential and trigonometric functions |
References:
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