科研之友
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摘要
Detailed analysis shows that a function f admits the double Jordan-type inequality if and only if f is analytic and even. Associated with f is the function g with f(x) = g(x(2)). In this short note, based on this association, and using properties of absolutely and/or (completely) monotonic functions, we propose a concise method to derive the inequality from the coefficients in the Taylor's series off. The results include some existing ones as special cases.
- 出版日期2012-3
- 单位浙江工商大学
