Articles containing proofs | Lemmas in group theory

Goursat's lemma

Goursat's lemma, named after the French mathematician Édouard Goursat, is an algebraic theorem about subgroups of the direct product of two groups. It can be stated more generally in a (and consequently it also holds in any Maltsev variety), from which one recovers a more general version of Zassenhaus' butterfly lemma. In this form, Goursat's theorem also implies the snake lemma. (Wikipedia).

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Proof of Lemma and Lagrange's Theorem

Please Subscribe here, thank you!!! https://goo.gl/JQ8Nys Proof of Lemma and Lagrange's Theorem. This video starts by proving that any two right cosets have the same cardinality. Then we prove Lagrange's Theorem which says that if H is a subgroup of a finite group G then the order of H div

From playlist Abstract Algebra

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Theory of numbers: Gauss's lemma

This lecture is part of an online undergraduate course on the theory of numbers. We describe Gauss's lemma which gives a useful criterion for whether a number n is a quadratic residue of a prime p. We work it out explicitly for n = -1, 2 and 3, and as an application prove some cases of Di

From playlist Theory of numbers

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Commutative algebra 47: Colimits and exactness

This lecture is part of an online course on commutative algebra, following the book "Commutative algebra with a view toward algebraic geometry" by David Eisenbud. We discuss the question of when a colimit of exact sequences is exact. We first show that a colimit of right exact sequences i

From playlist Commutative algebra

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Danylo Radchenko: Goursat rigid local systems of rank 4

The lecture was held within the framework of the Hausdorff Trimester Program: Periods in Number Theory, Algebraic Geometry and Physics. Abstract: I will talk about certain rigid local systems of rank 4 considered by Goursat, with emphasis on explicit constructions and examples. The talk i

From playlist Workshop: "Picard-Fuchs Equations and Hypergeometric Motives"

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Math 135 Complex Analysis Lecture 09 021715: Contour Integrals, Path Independence, Cauchy-Goursat

Examples of integration; Path independence theorem; Theorem of Cauchy-Goursat

From playlist Course 8: Complex Analysis

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Colloque d'histoire des sciences "Gaston Darboux (1842 - 1917)" - Hélène Gispert - 17/11/17

En partenariat avec le séminaire d’histoire des mathématiques de l’IHP Darboux c’est aussi le nom d’un journal : le Bulletin des sciences mathématiques (1869-1917) Hélène Gispert, GHDSO, Université Paris-Sud 11 À l’occasion du centenaire de la mort de Gaston Darboux, l’Institut Henri Poi

From playlist Colloque d'histoire des sciences "Gaston Darboux (1842 - 1917)" - 17/11/2017

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ME565 Lecture 3: Integration in the complex plane (Cauchy-Goursat Integral Theorem)

ME565 Lecture 3 Engineering Mathematics at the University of Washington Integration in the complex plane (Cauchy-Goursat Integral Theorem) Notes: http://faculty.washington.edu/sbrunton/me565/pdf/L03.pdf Course Website: http://faculty.washington.edu/sbrunton/me565/ http://faculty.wash

From playlist Engineering Mathematics (UW ME564 and ME565)

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Galois theory: Discriminants

This lecture is part of an online graduate course on Galois theory. We define the discriminant of a finite field extension, ans show that it is essentially the same as the discriminant of a minimal polynomial of a generator. We then give some applications to algebraic number fields. Corr

From playlist Galois theory

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Proof & Explanation: Gauss's Lemma in Number Theory

Euler's criterion: https://youtu.be/2IBPOI43jek One common proof of quadratic reciprocity uses Gauss's lemma. To understand Gauss's lemma, here we prove how it works using Euler's criterion and the Legendre symbol. Quadratic Residues playlist: https://www.youtube.com/playlist?list=PLug5Z

From playlist Quadratic Residues

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Berge's lemma, an animated proof

Berge's lemma is a mathematical theorem in graph theory which states that a matching in a graph is of maximum cardinality if and only if it has no augmenting paths. But what do those terms even mean? And how do we prove Berge's lemma to be true? == CORRECTION: at 7:50, the red text should

From playlist Summer of Math Exposition Youtube Videos

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Complex Analysis - Part 22 - Goursat's Theorem

Support the channel on Steady: https://steadyhq.com/en/brightsideofmaths Or support me via PayPal: https://paypal.me/brightmaths Or via Ko-fi: https://ko-fi.com/thebrightsideofmathematics Or via Patreon: https://www.patreon.com/bsom Or via other methods: https://thebrightsideofmathematics.

From playlist Complex Analysis

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Burnside's Lemma (Part 2) - combining math, science and music

Part 1 (previous video): https://youtu.be/6kfbotHL0fs Orbit-stabilizer theorem: https://youtu.be/BfgMdi0OkPU Burnside's lemma is an interesting result in group theory that helps us count things with symmetries considered, e.g. in some situations, we don't want to count things that can be

From playlist Traditional topics, explained in a new way

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Lie derivatives of differential forms

Introduces the lie derivative, and its action on differential forms. This is applied to symplectic geometry, with proof that the lie derivative of the symplectic form along a Hamiltonian vector field is zero. This is really an application of the wonderfully named "Cartan's magic formula"

From playlist Symplectic geometry and mechanics

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Math 135 Complex Analysis Lecture 10 021915: Cauchy Integral Formula

Extensions of Cauchy-Goursat on a rectangle; rectangle minus finitely many points; curves in an open disk; open disk minus finite number of points. Homotopic curves with fixed endpojnts; homotopic closed curves; deformation theorem. Winding number is an integer; Cauchy's Integral Formula

From playlist Course 8: Complex Analysis

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The Frobenius Problem - Method for Finding the Frobenius Number of Two Numbers

Goes over how to find the Frobenius Number of two Numbers.

From playlist ℕumber Theory

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Colloque d'histoire des sciences "Gaston Darboux (1842 - 1917)" - Philippe Nabonnand - 17/11/17

En partenariat avec le séminaire d’histoire des mathématiques de l’IHP Élie Cartan suit le cours de géométrie de Gaston Darboux Philippe Nabonnand, Archives Henri Poincaré, Université de Lorraine) À l’occasion du centenaire de la mort de Gaston Darboux, l’Institut Henri Poincaré souhaite

From playlist Colloque d'histoire des sciences "Gaston Darboux (1842 - 1917)" - 17/11/2017

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Graph regularity and counting lemmas - Jacob Fox

Conference on Graphs and Analysis Jacob Fox June 5, 2012 More videos on http://video.ias.edu

From playlist Mathematics

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Regularity methods in combinatorics, number theory, and computer science - Jacob Fox

Marston Morse Lectures Topic: Regularity methods in combinatorics, number theory, and computer science Speaker: Jacob Fox Affiliation: Stanford University Date: October 24, 2016 For more videos, visit http://video.ias.edu

From playlist Mathematics

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9. Szemerédi's graph regularity lemma IV: induced removal lemma

MIT 18.217 Graph Theory and Additive Combinatorics, Fall 2019 Instructor: Yufei Zhao View the complete course: https://ocw.mit.edu/18-217F19 YouTube Playlist: https://www.youtube.com/playlist?list=PLUl4u3cNGP62qauV_CpT1zKaGG_Vj5igX Prof. Zhao explains a strengthening of the graph regulari

From playlist MIT 18.217 Graph Theory and Additive Combinatorics, Fall 2019

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Riemann-Lebesgue Lemma

In this video, I prove the famous Riemann-Lebesgue lemma, which states that the Fourier transform of an integrable function must go to 0 as |z| goes to infinity. This is one of the results where the proof is more important than the theorem, because it's a very classical Lebesgue integral

From playlist Real Analysis

Related pages

Inverse function | Subdirect product | Complex analysis | Theorem | Group (mathematics) | Vertical line test | Schreier refinement theorem | Group isomorphism | Mathematical proof | Algebra | Relation (mathematics) | Maltsev variety | Direct product of groups | Function (mathematics) | Snake lemma | Édouard Goursat | Normal subgroup | Zassenhaus lemma | Subgroup | Group homomorphism | Projection (mathematics) | Kernel (algebra) | Graph of a function