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New Asymptotic Results on Fermat-Wiles Theorem
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作者 Kimou Kouadio Prosper Kouakou Kouassi Vincent Tanoé François 《Advances in Pure Mathematics》 2024年第6期421-441,共21页
We analyse the Diophantine equation of Fermat xp yp = zp with p > 2 a prime, x, y, z positive nonzero integers. We consider the hypothetical solution (a, b, c) of previous equation. We use Fermat main divisors, Dio... We analyse the Diophantine equation of Fermat xp yp = zp with p > 2 a prime, x, y, z positive nonzero integers. We consider the hypothetical solution (a, b, c) of previous equation. We use Fermat main divisors, Diophantine remainders of (a, b, c), an asymptotic approach based on Balzano Weierstrass Analysis Theorem as tools. We construct convergent infinite sequences and establish asymptotic results including the following surprising one. If z y = 1 then there exists a tight bound N such that, for all prime exponents p > N , we have xp yp zp. 展开更多
关键词 Fermat’s Last theorem Fermat-Wiles theorem Kimou’s Divisors Diophantine Quotient Diophantine Remainders Balzano Weierstrass Analysis theorem
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Small Modular Solutions to Fermat’s Last Theorem
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作者 Thomas Beatty 《Advances in Pure Mathematics》 2024年第10期797-805,共9页
The proof by Andrew Wiles of Fermat’s Last Theorem in 1995 resolved the existence question for non-trivial solutions in integers x,y,zto the equation xn+yn=znfor n>2. There are none. Surprisingly, there are infini... The proof by Andrew Wiles of Fermat’s Last Theorem in 1995 resolved the existence question for non-trivial solutions in integers x,y,zto the equation xn+yn=znfor n>2. There are none. Surprisingly, there are infinitely many solutions if the problem is recast in terms of modular arithmetic. Over a hundred years ago Issai Schur was able to show that for any n there is always a sufficiently large prime p0such that for all primes p≥p0the congruence xn+yn≡zn(modp)has a non-trivial solution. Schur’s argument wasnon-constructive, and there is no systematic method available at present to construct specific examples for small primes. We offer a simple method for constructing all possible solutions to a large class of congruences of this type. 展开更多
关键词 Fermat’s Last theorem Modular Arithmetic CONGRUENCEs Prime Numbers Primitive Roots Indices Ramsey Theory schur’s Lemma in Ramsey Theory
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Whole Perfect Vectors and Fermat’s Last Theorem
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作者 Ramon Carbó-Dorca 《Journal of Applied Mathematics and Physics》 2024年第1期34-42,共9页
A naïve discussion of Fermat’s last theorem conundrum is described. The present theorem’s proof is grounded on the well-known properties of sums of powers of the sine and cosine functions, the Minkowski norm de... A naïve discussion of Fermat’s last theorem conundrum is described. The present theorem’s proof is grounded on the well-known properties of sums of powers of the sine and cosine functions, the Minkowski norm definition, and some vector-specific structures. 展开更多
关键词 Fermat’s Last theorem Whole Perfect Vectors sine and Cosine Functions Natural and Rational Vectors Fermat Vectors
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基于S-R和分解定理的二维几何非线性问题的虚单元法求解
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作者 江巍 尹豪 +3 位作者 吴剑 汤艳春 李坤鹏 郑宏 《工程力学》 EI CSCD 北大核心 2024年第8期23-35,共13页
应变-旋转(Strain-Rotation,S-R)和分解定理为分析几何非线性问题提供了合理可靠的理论基础,但用有限元求解时会遇到大变形发生后的网格畸变问题。近年提出的虚单元法(Virtual element method,VEM)适用于一般的多边形网格,因此,该文尝... 应变-旋转(Strain-Rotation,S-R)和分解定理为分析几何非线性问题提供了合理可靠的理论基础,但用有限元求解时会遇到大变形发生后的网格畸变问题。近年提出的虚单元法(Virtual element method,VEM)适用于一般的多边形网格,因此,该文尝试使用一阶虚单元求解基于S-R和分解定理的二维几何非线性问题,以克服网格畸变的影响。基于重新定义的多项式位移空间基函数,推演获得一阶虚单元分析线弹性力学问题时允许位移空间向多项式位移空间的投影表达式;按照虚单元法双线性格式的计算规则,分析处理基于更新拖带坐标法和势能率原理的增量变分方程;进而建立离散系统方程及其矩阵表达形式,并编制MATLAB求解程序;采用常规多边形网格和畸变网格,应用该文算法分析均布荷载下的悬臂梁和均匀内压下的厚壁圆筒变形。结果与已有文献和ANSYS软件的对比表明:该文算法在两种网格中均可有效执行且具备足够数值精度。总体该文算法为基于S-R和分解定理的二维几何非线性问题求解提供了一种鲁棒方法。 展开更多
关键词 s-R和分解定理 虚单元法 几何非线性 网格畸变 多边形网格
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Fractional Noether theorem and fractional Lagrange equation of multi-scale mechano-electrophysiological coupling model of neuron membrane 被引量:1
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作者 王鹏 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第7期409-415,共7页
Noether theorem is applied to a variable order fractional multiscale mechano-electrophysiological model of neuron membrane dynamics.The variable orders fractional Lagrange equation of a multiscale mechano-electrophysi... Noether theorem is applied to a variable order fractional multiscale mechano-electrophysiological model of neuron membrane dynamics.The variable orders fractional Lagrange equation of a multiscale mechano-electrophysiological model of neuron membrane dynamics is given.The variable orders fractional Noether symmetry criterion and Noether conserved quantities are given.The forms of variable orders fractional Noether conserved quantities corresponding to Noether symmetry generators solutions of the model under different conditions are discussed in detail,and it is found that the expressions of variable orders fractional Noether conserved quantities are closely dependent on the external nonconservative forces and material parameters of the neuron. 展开更多
关键词 Hamilton’s principle Noether theorem fractional derivative multiscale electromechanical coupling neuron membrane
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参数化S谱幅值调制及轴承故障诊断应用
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作者 姜祖华 张坤 +1 位作者 杨欢 胥永刚 《西安交通大学学报》 EI CAS CSCD 北大核心 2024年第3期117-128,共12页
针对传统谱幅值调制方法易受噪声影响的问题,利用参数化S变换得到信号在时频域中的幅值,提出了一种参数化S谱幅值调制方法。该方法首先使用参数化S变换将信号转换到时频域并得到幅值和相位,然后将不同权重赋予时频域中的幅值以改变不同... 针对传统谱幅值调制方法易受噪声影响的问题,利用参数化S变换得到信号在时频域中的幅值,提出了一种参数化S谱幅值调制方法。该方法首先使用参数化S变换将信号转换到时频域并得到幅值和相位,然后将不同权重赋予时频域中的幅值以改变不同能量频率成分在信号中的占比,最后将调制后的幅值与原相位结合,使用参数化S逆变换重构一系列修正信号并计算其平方包络谱以提取故障特征。仿真和实验结果表明,该方法获得的幅值信息相比传统谱幅值调制方法更加准确和全面,对强噪声环境更具鲁棒性,能够有效实现滚动轴承的外圈、内圈和复合故障诊断。将所提方法与传统谱幅值调制方法和快速谱峭度方法进行对比,证明了参数化S谱幅值调制既能检测强噪声环境下的轴承故障信息,又能同时提取多种故障分量,在滚动轴承的故障特征提取中更具优越性。 展开更多
关键词 滚动轴承 故障诊断 谱幅值调制 参数化s谱幅值调制
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基于TDLAS的天然气泄漏范围重构方法
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作者 曹理想 文耀华 +2 位作者 张伯君 周泽华 业成 《激光与红外》 CAS CSCD 北大核心 2024年第9期1387-1391,共5页
可调谐半导体激光光谱(TDLAS)技术因其灵出色的灵敏度、精度和抗干扰性的特性,现已被广泛应用于场站天然气泄漏的监测工作。为克服单台TDLAS激光遥测仪无法获得泄漏气体扩散影响范围的局限性,本文提出了一种基于多台TDLAS遥测仪协同的... 可调谐半导体激光光谱(TDLAS)技术因其灵出色的灵敏度、精度和抗干扰性的特性,现已被广泛应用于场站天然气泄漏的监测工作。为克服单台TDLAS激光遥测仪无法获得泄漏气体扩散影响范围的局限性,本文提出了一种基于多台TDLAS遥测仪协同的智能监测方法,通过在不同斜平面内对泄漏气团进行扫查,依据Brianchon定理获得不同斜平面内气体泄漏的外轮廓方程,重构天然气的三维空间泄漏影响区域,实时开展监测与预警。 展开更多
关键词 天然气 TDLAs 泄漏监测 Brianchon定理
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Products of Odd Numbers or Prime Number Can Generate the Three Members’ Families of Fermat Last Theorem and the Theorem Is Valid for Summation of Squares of More Than Two Natural Numbers
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作者 Susmita Pramanik Deepak Kumar Das Panchanan Pramanik 《Advances in Pure Mathematics》 2023年第10期635-641,共7页
Fermat’s last theorem, had the statement that there are no natural numbers A, B, and C such that A<sup>n</sup> + B<sup>n</sup> = C<sup>n</sup>, in which n is a natural number great... Fermat’s last theorem, had the statement that there are no natural numbers A, B, and C such that A<sup>n</sup> + B<sup>n</sup> = C<sup>n</sup>, in which n is a natural number greater than 2. We have shown that any product of two odd numbers can generate Fermat or Pythagoras triple (A, B, C) following n = 2 and also it is applicable A<sup>2</sup> + B<sup>2</sup> + C<sup>2</sup> + D<sup>2</sup> + so on =A<sub>n</sub><sup>2 </sup>where all are natural numbers. 展开更多
关键词 Fermat Last theorem Generation of Fermat’s Numbers Extension of Fermat’s Expression Fermat’s Expression from Products of Odd Numbers
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N次幂下S-凸函数和其性质研究
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作者 刘明术 方宏彬 《池州学院学报》 2024年第3期6-9,共4页
以凸函数、S-凸函数、平方凸函数、平方S-凸函数的定义和性质为研究基础,根据从平方凸函数到平方S-凸函数的演变推进过程,采用了凸函数概念的代数不等式形式,给出了N次幂下S-凸函数的概念,并对其判别定理和性质进行了讨论,定义并证明了... 以凸函数、S-凸函数、平方凸函数、平方S-凸函数的定义和性质为研究基础,根据从平方凸函数到平方S-凸函数的演变推进过程,采用了凸函数概念的代数不等式形式,给出了N次幂下S-凸函数的概念,并对其判别定理和性质进行了讨论,定义并证明了N次幂下S-凸函数的Jensen型不等式。研究表明,N次幂下S-凸函数包含了凸函数、平方凸函数、平方S-凸函数的性质,是凸函数的一种广义凸函数的推广,开辟了全新的推广途径。 展开更多
关键词 JENsEN不等式 s-凸函数 平方凸函数 平方s-凸函数 判别定理
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On Fermat Last Theorem: The New Efficient Expression of a Hypothetical Solution as a Function of Its Fermat Divisors
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作者 Prosper Kouadio Kimou 《American Journal of Computational Mathematics》 2023年第1期82-90,共9页
Denote by a non-trivial primitive solution of Fermat’s equation (p prime).We introduce, for the first time, what we call Fermat principal divisors of the triple defined as follows. , and . We show that it is possible... Denote by a non-trivial primitive solution of Fermat’s equation (p prime).We introduce, for the first time, what we call Fermat principal divisors of the triple defined as follows. , and . We show that it is possible to express a,b and c as function of the Fermat principal divisors. Denote by the set of possible non-trivial solutions of the Diophantine equation . And, let<sub></sub><sub></sub> (p prime). We prove that, in the first case of Fermat’s theorem, one has . In the second case of Fermat’s theorem, we show that , ,. Furthermore, we have implemented a python program to calculate the Fermat divisors of Pythagoreans triples. The results of this program, confirm the model used. We now have an effective tool to directly process Diophantine equations and that of Fermat. . 展开更多
关键词 Fermat’s Last theorem Fermat Divisors Barlow’s Relations Greatest Common Divisor
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A Proof of Brouwer’s Fixed Point Theorem Using Sperner’s Lemma
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作者 Cassie Lu 《数学计算(中英文版)》 2023年第2期1-6,共6页
This article offers a simple but rigorous proof of Brouwer’s fixed point theorem using Sperner’s Lemma.The general method I have used so far in the proof is mainly to convert the n-dimensional shapes to the correspo... This article offers a simple but rigorous proof of Brouwer’s fixed point theorem using Sperner’s Lemma.The general method I have used so far in the proof is mainly to convert the n-dimensional shapes to the corresponding case under the Sperner’s Labeling and apply the Sperner’s Lemma to solve the question. 展开更多
关键词 Brouwer’s Fixed Point theorem sperner’s Lemma PROOF
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Gravitation, Density Upper Limit and Quantization of Space
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作者 Doron Kwiat 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第2期534-545,共12页
The singularity at distance r → 0 at the center of a spherically symmetric non-rotating, uncharged mass of radius R, is considered here. Under inverse square law force, the Schwarzschild metric, needs to be modified,... The singularity at distance r → 0 at the center of a spherically symmetric non-rotating, uncharged mass of radius R, is considered here. Under inverse square law force, the Schwarzschild metric, needs to be modified, to include Newton’s Shell Theorem (NST). By including NST for r, both Schwarzschild singularity at r = 2GM/c2 and at r → 0 singularities are removed from the metric. Near R → 0, the question of maximal density is considered based on Schwarzschild’s modified metric, and compared to the quantum limit of maximal mass density put by Planck’s quantum-based universal units. It is asserted, that General relativity, when combined with Planck’s universal units, inevitably leads to quantization of gravity. 展开更多
关键词 GRAVITATION shell theorem sINGULARITY schwarzschild Radius CGH Physics: Planck’s scale
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具有饱和恢复率的SEIR时滞模型的行波解
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作者 卫珍妮 《西北师范大学学报(自然科学版)》 2024年第1期20-29,共10页
研究一类具有饱和恢复率的SEIR时滞模型的行波解.首先,考虑一类二维系统初值问题的适定性;然后,通过构造一对有界的向量值上、下解得到一个闭凸集;最后,利用Schauder不动点定理证明:当基本再生数R^(0)>1,波速c>c^(*)时模型存在非... 研究一类具有饱和恢复率的SEIR时滞模型的行波解.首先,考虑一类二维系统初值问题的适定性;然后,通过构造一对有界的向量值上、下解得到一个闭凸集;最后,利用Schauder不动点定理证明:当基本再生数R^(0)>1,波速c>c^(*)时模型存在非平凡行波解. 展开更多
关键词 sEIR模型 饱和恢复率 时滞 行波解 sCHAUDER不动点定理
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Investigation of Probability Generating Function in an Interdependent <i>M/M/</i>1:(∞;GD) Queueing Model with Controllable Arrival Rates Using Rouche’s Theorem
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作者 Vishwa Nath Maurya 《Open Journal of Optimization》 2012年第2期34-38,共5页
Present paper deals a M/M/1:(∞;GD) queueing model with interdependent controllable arrival and service rates where- in customers arrive in the system according to poisson distribution with two different arrivals rate... Present paper deals a M/M/1:(∞;GD) queueing model with interdependent controllable arrival and service rates where- in customers arrive in the system according to poisson distribution with two different arrivals rates-slower and faster as per controllable arrival policy. Keeping in view the general trend of interdependent arrival and service processes, it is presumed that random variables of arrival and service processes follow a bivariate poisson distribution and the server provides his services under general discipline of service rule in an infinitely large waiting space. In this paper, our central attention is to explore the probability generating functions using Rouche’s theorem in both cases of slower and faster arrival rates of the queueing model taken into consideration;which may be helpful for mathematicians and researchers for establishing significant performance measures of the model. Moreover, for the purpose of high-lighting the application aspect of our investigated result, very recently Maurya [1] has derived successfully the expected busy periods of the server in both cases of slower and faster arrival rates, which have also been presented by the end of this paper. 展开更多
关键词 Interdependent QUEUEING Model BIVARIATE Poisson Process Controllable Arrival Rates Probability Generating Function Laplace Transform Rouche’s theorem Performance Measures
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Rothe’s Fixed Point Theorem and the Controllability of the Benjamin-Bona-Mahony Equation with Impulses and Delay
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作者 Hugo Leiva Jose L. Sanchez 《Applied Mathematics》 2016年第15期1748-1764,共18页
For many control systems in real life, impulses and delays are intrinsic phenomena that do not modify their controllability. So we conjecture that under certain conditions the abrupt changes and delays as perturbation... For many control systems in real life, impulses and delays are intrinsic phenomena that do not modify their controllability. So we conjecture that under certain conditions the abrupt changes and delays as perturbations of a system do not destroy its controllability. There are many practical examples of impulsive control systems with delays, such as a chemical reactor system, a financial system with two state variables, the amount of money in a market and the savings rate of a central bank, and the growth of a population diffusing throughout its habitat modeled by a reaction-diffusion equation. In this paper we apply the Rothe’s Fixed Point Theorem to prove the interior approximate controllability of the following Benjamin Bona-Mohany(BBM) type equation with impulses and delay where and are constants, Ω is a domain in , ω is an open non-empty subset of Ω , denotes the characteristic function of the set ω , the distributed control , are continuous functions and the nonlinear functions are smooth enough functions satisfying some additional conditions. 展开更多
关键词 Interior Approximate Controllability Benjamin Bona-Mohany Equation with Impulses and Delay strongly Continuous semigroup Rothe’s Fixed Point theorem
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数论中的Wilson定理通过群论中的Cauchy定理的证明
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作者 张海诚 《高等数学研究》 2024年第5期93-93,F0003,共2页
本文利用近世代数课程中有限群的Cauchy定理证明数论课程里的Wilson定理.
关键词 数论 WILsON定理 群论 CAUCHY定理
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S形钢丝初辊压工艺的数值分析
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作者 赵远 贾力 +5 位作者 胡丞杨 周能作 王飞 朱晓雄 薛花娟 赵军 《现代交通与冶金材料》 CAS 2024年第5期17-23,共7页
根据主缆S形钢丝的技术指标要求,利用有限元分析和试验测试等手段,在保持总变形不变的条件下,对10#钢分别进行4道、6道、8道初辊压测试试验。试验结果表明S形钢丝应力的集中区域存在于变形过渡区和辊缝中心线的主要变形区,随着辊压道次... 根据主缆S形钢丝的技术指标要求,利用有限元分析和试验测试等手段,在保持总变形不变的条件下,对10#钢分别进行4道、6道、8道初辊压测试试验。试验结果表明S形钢丝应力的集中区域存在于变形过渡区和辊缝中心线的主要变形区,随着辊压道次的增加,拉长的晶粒也更多。数值分析的预测结果与实验表征的结果具有良好的一致性。 展开更多
关键词 初辊压 s形钢丝 有限元分析 应力-应变
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S模式二次雷达询问策略的研究和改进
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作者 咸儆醒 张继明 +1 位作者 周进 卓齐刚 《信息化研究》 2024年第2期1-6,33,共7页
通常常规二次雷达(SSR)工作在A/C模式,S模式二次雷达工作在交互模式,通过不同的询问策略获得应答信号。在实际应用中发现,特殊应答机对于交互模式的应答存在丢点问题。本文通过对现有S模式二次雷达询问策略的分析和研究,在国际民航组织... 通常常规二次雷达(SSR)工作在A/C模式,S模式二次雷达工作在交互模式,通过不同的询问策略获得应答信号。在实际应用中发现,特殊应答机对于交互模式的应答存在丢点问题。本文通过对现有S模式二次雷达询问策略的分析和研究,在国际民航组织二次雷达规范的基础上提出了改进的询问策略,解决了S模式二次雷达与传统A/C模式二次雷达兼容过程中偶尔出现的目标丢失问题,为S模式二次雷达的运用提供了建设性意见。 展开更多
关键词 二次雷达 A/C模式 s模式 联合模式 全呼询问 点名询问
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Ground roll attenuation using a time-frequency dependent polarization filter based on the S transform 被引量:6
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作者 谭玉阳 何川 +1 位作者 王艳冬 赵忠 《Applied Geophysics》 SCIE CSCD 2013年第3期279-294,358,共17页
The ground roll and body wave usually show significant differences in arrival time, frequency content, and polarization characteristics, and conventional polarization filters that operate in either the time or frequen... The ground roll and body wave usually show significant differences in arrival time, frequency content, and polarization characteristics, and conventional polarization filters that operate in either the time or frequency domain cannot consider all these elements. Therefore, we have developed a time-frequency dependent polarization filter based on the S transform to attenuate the ground roll in seismic records. Our approach adopts the complex coefficients of the S transform of the multi-component seismic data to estimate the local polarization attributes and utilizes the estimated attributes to construct the filter function. In this study, we select the S transform to design this polarization filter because its scalable window length can ensure the same number of cycles of a Fourier sinusoid, thereby rendering more precise estimation of local polarization attributes. The results of applying our approach in synthetic and real data examples demonstrate that the proposed polarization filter can effectively attenuate the ground roll and successfully preserve the body wave. 展开更多
关键词 Ground roll s transform spectral matrix polarization attributes polarization filter
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用区间套定理证明Rolle定理、Lagrange定理 被引量:6
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作者 许在库 《安徽大学学报(自然科学版)》 CAS 2003年第2期18-21,共4页
Rolle定理和Lagarange定理是两个重要的微分中值定理,它们是Cauchy定理的基础,进一步为L'Hospital法则求极限提供了理论依据.它们还是研究函数增减性、凹凸性的基础.它在整个微分学中起着把微分的概念和方法应用于许多数学物理问题... Rolle定理和Lagarange定理是两个重要的微分中值定理,它们是Cauchy定理的基础,进一步为L'Hospital法则求极限提供了理论依据.它们还是研究函数增减性、凹凸性的基础.它在整个微分学中起着把微分的概念和方法应用于许多数学物理问题的桥梁作用.本文用区间套定理给出它的另一种证明. 展开更多
关键词 区间套定理 Ro11e定理 LAGRANGE定理 微分中值定理 微分学 CAUCHY定理 L'Hospital法则
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