Proof theory | Theorems in the foundations of mathematics

Cut-elimination theorem

The cut-elimination theorem (or Gentzen's Hauptsatz) is the central result establishing the significance of the sequent calculus. It was originally proved by Gerhard Gentzen in his landmark 1934 paper "Investigations in Logical Deduction" for the systems LJ and LK formalising intuitionistic and classical logic respectively. The cut-elimination theorem states that any judgement that possesses a proof in the sequent calculus making use of the cut rule also possesses a cut-free proof, that is, a proof that does not make use of the cut rule. (Wikipedia).

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Solve a System of Equations Using Elimination

👉Learn how to solve a system (of equations) by elimination. A system of equations is a set of equations which are collectively satisfied by one solution of the variables. The elimination method of solving a system of equations involves making the coefficient of one of the variables to be e

From playlist Solve a System of Equations Using Elimination | Hard

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Graphing a System of Equations by Eliminating the Fractions

👉Learn how to solve a system (of equations) by elimination. A system of equations is a set of equations which are collectively satisfied by one solution of the variables. The elimination method of solving a system of equations involves making the coefficient of one of the variables to be e

From playlist Solve a System of Equations Using Elimination | Hard

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Using Multipliers to Solve a System of Equations Using Elimination

👉Learn how to solve a system (of equations) by elimination. A system of equations is a set of equations which are collectively satisfied by one solution of the variables. The elimination method of solving a system of equations involves making the coefficient of one of the variables to be e

From playlist Solve a System of Equations Using Elimination | Hard

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Will Troiani - Proofs as permutations (Geometry of Interaction 0)

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From playlist Computation, Geometry, Logic seminar

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Using Two Multipliers to Solve a System of Equations with Elimination

👉Learn how to solve a system (of equations) by elimination. A system of equations is a set of equations which are collectively satisfied by one solution of the variables. The elimination method of solving a system of equations involves making the coefficient of one of the variables to be e

From playlist Solve a System of Equations Using Elimination | Hard

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Toward an imaginary Ax-Kochen-Ershov principle - S. Rideau - Workshop 2 - CEB T1 2018

Silvain Rideau (CNRS – Université Paris Diderot) / 09.03.2018 Toward an imaginary Ax-Kochen-Ershov principle. All imaginaries that have been classified in Henselian fields (possibly with operators) have been shown to be geometric in the sense of Haskell-HrushovskiMacpherson. In general,

From playlist 2018 - T1 - Model Theory, Combinatorics and Valued fields

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How to Solve a System by Using Two Multipliers for Elimination

👉Learn how to solve a system (of equations) by elimination. A system of equations is a set of equations which are collectively satisfied by one solution of the variables. The elimination method of solving a system of equations involves making the coefficient of one of the variables to be e

From playlist Solve a System of Equations Using Elimination | Hard

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MAG - Lecture 9 - The Elimination Theorem

metauni Algebraic Geometry (MAG) is a first course in algebraic geometry, in Roblox. In Lecture 9 we discuss the Elimination Theorem and give some examples of using it to solve systems of polynomial equations. The webpage for MAG is https://metauni.org/mag/. This video was recorded in Th

From playlist MAG

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Nonlinear algebra, Lecture 3: "Elimination and Implicitization", by Bernd Sturmfels

This is the third lecture in the IMPRS Ringvorlesung, the advanced graduate course at the Max Planck Institute for Mathematics in the Sciences.

From playlist IMPRS Ringvorlesung - Introduction to Nonlinear Algebra

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MAG - Lecture 8 - Buchberger's algorithm and Elimination Theory Part 1

metauni Algebraic Geometry (MAG) is a first course in algebraic geometry, in Roblox. In Lecture 8 we give the Buchberger algorithm for constructing Grobner bases, and begin elimination theory. The webpage for MAG is https://metauni.org/mag/. This video was recorded in The Rising Sea (htt

From playlist MAG

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Shadows of Computation - Lecture 1 - Making subtle ideas apparent

Welcome to Shadows of Computation, an online course taught by Will Troiani and Billy Snikkers, covering the foundations of category theory and how it is used by computer scientists to abstract computing systems to reveal their intrinsic mathematical properties. In the first lecture Will in

From playlist Shadows of Computation

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Solve a System of Linear Equations Using Elimination

👉Learn how to solve a system (of equations) by elimination. A system of equations is a set of equations which are collectively satisfied by one solution of the variables. The elimination method of solving a system of equations involves making the coefficient of one of the variables to be e

From playlist Solve a System of Equations Using Elimination | Hard

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Zlil Sela - Envelopes and equivalence relations in a free group

Zlil Sela (Hebrew University of Jerusalem, Israel) We study and classify all the definable equivalence relations in a free (and a torsion-free hyperbolic) group. To do that we associate a Diophantine set with every definable set, that contains the definable set, and its generic points are

From playlist T1-2014 : Random walks and asymptopic geometry of groups.

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Gilles Dowek : La difficile explication des résultats des calculs : des preuves automatiques à ...

Recording during the thematic meeting : "Algorithm and Programming" the May 2, 2017 at the Centre International de Rencontres Mathématiques (Marseille, France) Filmmaker: Guillaume Hennenfent Find this video and other talks given by worldwide mathematicians on CIRM's Audiovisual Mathemat

From playlist Logic and Foundations

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Pushing back the barrier of imperfection - F-V. Kuhlmann - Workshop 2 - CEB T1 2018

Franz-Viktor Kuhlmann (Szczecin) / 06.03.2018 The word “imperfection” in our title not only refers to fields that are not perfect, but also to the defect of valued field extensions. The latter is not necessarily directly connected with imperfect fields but may always appear when at least

From playlist 2018 - T1 - Model Theory, Combinatorics and Valued fields

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How to Solve a System of Equations Using Elimination with Fractions

👉Learn how to solve a system (of equations) by elimination. A system of equations is a set of equations which are collectively satisfied by one solution of the variables. The elimination method of solving a system of equations involves making the coefficient of one of the variables to be e

From playlist Solve a System of Equations Using Elimination | Hard

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Using two multipliers when solving a system of equations using the addition method

👉Learn how to solve a system (of equations) by elimination. A system of equations is a set of equations which are collectively satisfied by one solution of the variables. The elimination method of solving a system of equations involves making the coefficient of one of the variables to be e

From playlist Solve a System of Equations Using Elimination | Hard

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How to Use Elimination to Solve a System of Equations

👉Learn how to solve a system (of equations) by elimination. A system of equations is a set of equations which are collectively satisfied by one solution of the variables. The elimination method of solving a system of equations involves making the coefficient of one of the variables to be e

From playlist Solve a System of Equations Using Elimination | Hard

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Solving a system of equations with infinite many solutions

👉Learn how to solve a system (of equations) by elimination. A system of equations is a set of equations which are collectively satisfied by one solution of the variables. The elimination method of solving a system of equations involves making the coefficient of one of the variables to be e

From playlist Solve a System of Equations Using Elimination | Medium

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Stepan Kuznetsov: Relational models for the Lambek calculus with intersection and unit

HYBRID EVENT Recorded during the meeting "19th International Conference on Relational and Algebraic Methods in Computer Science" the November 5, 2021 by the Centre International de Rencontres Mathématiques (Marseille, France) Filmmaker: Guillaume Hennenfent Find this video and other t

From playlist Logic and Foundations

Related pages

Proof theory | Tautology (logic) | Analytic proof | Prolog | Sequent calculus | Intuitionistic logic | Lemma (mathematics) | Gentzen's consistency proof | Proof-theoretic semantics | Craig interpolation | Classical logic | Contradiction | Sequent | Deduction theorem | George Boolos | Admissible rule