包含函数Γ（x）的对数完全单调函数及不等式

基于欧拉Gamma函数的奇特性质,利用函数的单调性理论以及一些简单函数的积分表达式与级数展开式证明了函数f_α(x),α∈R和函数s(x)的对数完全单调性,并利用该性质得出了一个比原有结论更精确的不等式以及一个双边不等式.     

一些特殊函数的完全单调性

欧拉Gamma函数是一种非常重要的函数,在数学的许多分支以及物理、工程等学科中都有着十分重要的作用.而完全单调性以及对数完全单调性是Gamma函数的重要性质.主要证明了一些包含Gamma函数和Psi函数在内的特殊函数的完全单调性和对数完全单调性,并由此推出了一些重要的不等式.     

两个Gamma商函数的对数完全单调性

主要研究了Gamma商函数的对数完全单调性.通过引入一个新的辅助函数证明了一类Gamma商函数是严格对数完全单调的,对此类函数的系数进行了推广并证明了推广后的这类Gamma商函数也是严格对数完全单调的.     

与Gamma函数有关的对数完全单调函数及其应用

为了完善函数G_(α,β)(x)(其中参数α∈R,β≥0)及函数1/G_(α,β)(x)在区间(0,∞)上的对数完全单调性和相关不等式,利用Taylor展开式、Gamma函数、Psi函数的级数表达式和积分表达式研究了函数G_(α,β)(x)和函数1/G_(α,β)(x)数的对数完全单调性,将函数G_(α,β)(x)和函数1/G_(α,β)(x)对数完全单调的充分条件扩大;利用对数完全单调性得到新的不等式,并通过对特殊情形的研究,得到一个形式简单对称的双边不等式,该不等式对阶乘数之乘积与∏nk=1k~k的商做出估计.     

关于伽玛函数的单调性质

伽玛函数的单调性质和对数完全单调性质被获得了.     

一类不可导函数的单调性

利用Schw arz导数的相关知识,讨论了一类不可导函数的单调性,并给出几个重要且实用的结论.     

包含q-psi函数的函数完全单调性及其应用

主要证明了涉及q-digamma函数的完全单调性.通过引入经典q-理论将包含digamma函数的函数进行q-模拟,利用q-模拟函数以及级数的性质,得到了包含q-digamma函数的完全单调性.最后利用它们的完全单调性得到了有关q-digamma和q-trigamma函数的不等式.     

关于一个完全单调函数

设α>0和β是实数,则函数1+αxx+β在(0,∞)上是完全单调的充要条件是α≤2β.这推广了已有的结果.     

如何用导数判断函数单调性

函数的单调性是函数的重要性质,也是高考的热点问题,若利用函数定义求解,一般较为复杂．但是利用导数求函数的单调就有效地解决了这一难题．     

如何用导数解决含参函数的单调性问题

1提出问题我们在解决单调性问题中，常常遇到一类含有参数的函数（简称含参函数）在某区间单调问题：     

A logarithmically completely monotonic function involving the ratio of gamma functions

In the paper, the authors concisely survey and review some functionsinvolving the gamma function and its various ratios, simply state theirlogarithmically complete monotonicity and related results, and find necessaryand sufficient conditions for a new function involving the ratio of twogamma functions and originating from the coding gain to be logarithmicallycompletely monotonic.     

Logarithmically completely monotonic functions relating to the gamma function

In this paper, the logarithmically complete monotonicity of the function exΓ(x+β)/xx+β−α in (0,∞) for α∈R and β?0 is considered and the corresponding result by G.D. Anderson, R.W. Barnard, K.C. Richards, M.K. Vamanamurthy and M. Vuorinen is generalized. As applications of these results, some inequalities between identric mean and ratio of two gamma functions by J.D. Ke?ki? and P.M. Vasi? are extended.     

A certain function class related to the class of logarithmically completely monotonic functions

In this article, we introduce and investigate the notion of strongly logarithmically completely monotonic functions. Among other results, we present some properties and relationships involving this function class and several closely-related function classes.     

A class of logarithmically completely monotonic functions associated with the gamma function

In this article, a necessary condition, several sufficient conditions and a sufficient and necessary condition for a class of functions involving the gamma function to be logarithmically completely monotonic are established, and then some known results are extended.     

Some classes of completely monotonic functions, II

A function is said to be completely monotonic if for all x > 0 and n = 0,1,2,.... In this paper we present several new classes of completely monotonic functions. Our functions have in common that they are defined in terms of the classical gamma, digamma, and polygamma functions. Moreover, we apply one of our monotonicity theorems to prove a new inequality for prime numbers. Some of the given results extend and complement theorems due to Bustoz & Ismail, Clark & Ismail, and other researchers. 2000 Mathematics Subject Classification Primary—11A41, 26A48, 33B15; Secondary—26D15     

A complete monotonicity property of the gamma function

A logarithmically completely monotonic function is completely monotonic. The function is strictly completely monotonic on (0,∞). The function is strictly logarithmically completely monotonic on (0,∞).     

A function class of strictly positive definite and logarithmically completely monotonic functions related to the modified Bessel functions

In this paper, we give some conditions for a class of functions related to Bessel functions to be positive definite or strictly positive definite. We present some properties and relationships involving logarithmically completely monotonic functions and strictly positive definite functions. In particular, we are interested with the modified Bessel functions of the second kind. As applications, we prove the logarithmically monotonicity for a class of functions involving the modified Bessel functions of second kind and we established new inequalities for this function.