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1.
本文给出并论证了积分中值定理中的ξ,当 b→a~+时,将趋于(a,b)的中点,即·第一,二积分中值定理中的ξ分别有积分中值定理若函数 f(x)在区间[a,b]上连续,则在[a,b]上至少存在一点ξ,使得  相似文献   

2.
郑美华 《科技信息》2007,(12):126-126
本文讨论当积分区间长度趋于无穷大,被积函数f(x)具有性质limx→+∞f(x)1nx=d≠0。其积分中值定理中间值ξ其中的渐进性质。  相似文献   

3.
关于积分第一中值定理   总被引:2,自引:0,他引:2  
关于积分第一中值定理(推广了的形式)的叙述,二十多年来,我国高等学校理科采用的各种版本,基本上大同小异。例如,有如下的叙述方式:定理1 设在区间[a,b]上函数f(x)连续而g(x)可积,并且g(x)在整个区间[a,b]上不变号。则有一点ξ∈[a,b]使  相似文献   

4.
对积分中值定理给出了一点注记,即积分中值定理的中值点ξ可以在积分区间内部取得。同时对ξ的位置进行了估计。  相似文献   

5.
泛函微分方程(超中立型)稳定性的基本理论   总被引:1,自引:0,他引:1  
本文研究泛函微分方程(超中立型)的稳定性,得到稳定的和不稳定的充分条件。推广了[1]、[2]的结果,并推广了[3]第五章中之定理4·1、4·2。本文定理1·3用条件 V(ξ)≤V(t)代替条件 V(ξ)≤P(V(t)),t-r≤ξ≤t,P(s)>s(函数 P(s)一般很难求,这在[4]P.63中已指出)。本文定理1·4利用常微分方程中的 Liapunov 函数的性质结合定理1·3得到判定稳定性的简便方法。本文还研究了第二类型的泛函微分方程(右端之积分项其积分区间为[t_0,t])的稳定性(在过去的资料中尚未见到;只见到关于这类方程解的存在与唯一性论文如[5])  相似文献   

6.
对Rolle中值定理的条件作了改进,把函数可导推广为左或右可导,把有限区间推广为无限区间,把函数在区间端点处的函数值相等推广为可以不等.主要建立了如下的推广定理:设函数f(x)在有限或无限区间(a,b)上连续,f(x)在(a,b)内右(或左)可导,并存在{an},{bn}包括(a,b)使 liman n→∞=a limbn n→∞=b limf(an)n→∞=linf(bn)n→∞=A A为实数或±∞,则存在ξ,η∈(a,b),使得f′+(ξ)≥0,f′+(η)≤0(或f′-(ξ)≥0,f′-(η)≤0。更进一步,设f′+(x)(或f′-(x))在(a,b)内左(或右)连续,则存在ξ∈(a,b)使得f′+(ξ)=0(或f′-(ξ)=0).  相似文献   

7.
有关中值定理中间点位置的两个定理   总被引:2,自引:0,他引:2  
对于∪+∞i=1[ai,ai+1)=[0,+∞),aiai+1=I(I可为任意确定的正数),i=1,2,…,给出了一类单调函数u(x),x>0在区间[ai,ai+1],i=1,2,…的拉格朗日中值定理中间点(设为ξi,i=1,2,…)的位置随i值单增而变化的规律。并且对于函数u(x)在任意区间内的中间点的位置给出了一个上界。  相似文献   

8.
利用区间序列的性质以及极限基础理论研究了微分中值定理中ξ的趋近性质,并证明了Lagrange中值定理中当ab,相互靠近时其中间值ξ→x0的渐进性质.  相似文献   

9.
利用介值定理和拉格朗日中值定理证明了命题:设函数f(x)在[0,1]上连续,在(0,1)内可导,且f ′(x)>0, f(0)=0, f(1)=1,则存在ξ1,ξ2∈(0,1),使得1/f′(ξ1)+1/f′(ξ2)=2。通过对命题证明过程的分析,对命题进行了推广。  相似文献   

10.
本文建立了有界线性算子的一种函数演算,并得到了这种演算的谱映射定理: 引理1 设T∈D(X)-B(X),ρ(T)≠Φ,则存在S∈B(X)及ξ∈C,λ∈σ_c(S),使T=f_(ξ,λ)(S) 定理1 设T∈B(X),则对ξ∈C,λ∈σ_c(T), 我们有: 1)σ(f_(ξ,λ)(T))=f_(ξ,λ)(σ(T)); 2)σ(f_(ξ,λ)(T)(x)=f_(ξ,λ)(σ_T(x)),x∈X 通过这种演算,可以把无界封闭线性算子表示成有界线性算子函数。利用这种函数演算和相应的谱映射定理,我们证明了无界封闭线性算子是可分解(谱)算子的充要条件是它是有界可分解(谱)算子的函数。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of  相似文献   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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