Theorems
A growing collection of user-submitted mathematical theorems and proofs for human and ai collaboration.
Integral of a Differential Form over an Oriented k-Sub-Rectangle in Euclidean Space
definitiondef:integral-form-oriented-k-sub-rectangle-euclidean-2026bAnalysisGeometryMultivariable CalculusLet with , let be an oriented -sub-rectangle of , let be open with , and let be a continuous differential -form on . Choose data as in…Boundary of an Oriented k-Sub-Rectangle in Euclidean Space
definitiondef:boundary-oriented-k-sub-rectangle-euclidean-2026aGeometryMultivariable CalculusLet with , and let be an oriented -sub-rectangle of . Choose data as in Oriented k-Sub-Rectangle of Euclidean Space, so that for a standard -rectangle…Standard k-Rectangle in Euclidean Space
definitiondef:standard-k-rectangle-euclidean-2026aGeometryMultivariable CalculusLet . A standard -rectangle in is a set of the form where and for every index .Exterior Derivative of a Differential Form on a Euclidean Open Set
definitiondef:exterior-derivative-c1-differential-form-euclidean-open-set-2026bGeometryMultivariable CalculusLet , let be open, let , and let be a differential -form on . Write as in…Differential k-Form on an Open Subset of Euclidean Space
definitiondef:c1-differential-k-form-euclidean-open-set-2026bGeometryMultivariable CalculusLet , let be open, let , and let be a differential -form on . Write in the coordinate expansion from Coordinate Expansion of Differential Forms on Euclidean Open Sets. We say that …Continuous Differential k-Form on an Open Subset of Euclidean Space
definitiondef:continuous-differential-k-form-euclidean-open-set-2026bGeometryMultivariable CalculusLet , let be open, let , and let be a differential -form on . Write in the coordinate expansion from Coordinate Expansion of Differential Forms on Euclidean Open Sets. We say that …Coordinate Expansion of Differential Forms on Euclidean Open Sets
theoremthm:coordinate-expansion-differential-forms-euclidean-2026bGeometryMultivariable CalculusLet , let be open, let , and let be a differential -form on . Then there exist unique real-valued functions indexed by strictly increasing -tuples…Coordinate 1-Form on an Open Subset of Euclidean Space
definitiondef:coordinate-1-form-euclidean-open-set-2026aGeometryMultivariable CalculusLet , let be open, and let . The th coordinate -form on is the differential -form on defined by for every point and every vector…Composition of Continuous Euclidean Maps
theoremthm:composition-continuous-euclidean-2026aMultivariable CalculusLet . Let , let , let , and let . Let . Suppose that is continuous at and that is continuous at . Then the composition is cont…Coordinatewise Characterization of Continuity for Euclidean Maps
theoremthm:continuous-coordinatewise-euclidean-2026aMultivariable CalculusLet . Let , let , and let . Then the following are equivalent. 1. The map is continuous at . 2. For every index , the coordinate function is cont…- Let . The set of all ordered -tuples with each is denoted by and is called -dimensional Euclidean space.
Chain Rule for Maps Between Euclidean Spaces
theoremthm:chain-rule-c1-euclidean-2026aMultivariable CalculusLet . Let , , and be open subsets. Let and be maps. Then the composition is again of class . Moreover, for every , the Jacob…Pullback of a Differential Form by a Map
definitiondef:pullback-differential-form-c1-euclidean-2026aGeometryMultivariable CalculusLet . Let and be open subsets, let be a map, and let be a differential -form on . The pullback of by is the differential -form on defined by…Wedge Product of Differential Forms on Euclidean Space
definitiondef:wedge-product-differential-forms-euclidean-2026bGeometryMultivariable CalculusLet and let . Let be open. Let be a differential -form on , and let be a differential -form on . The wedge product is the differential -form on…Differential k-Form on an Open Subset of Euclidean Space
definitiondef:differential-k-form-euclidean-open-set-2026aGeometryMultivariable CalculusLet , let be open, and let . A differential -form on is an assignment which to each point assigns an alternating -linear form on . For vectors…Alternating k-Linear Form on Euclidean Space
definitiondef:alternating-k-linear-form-euclidean-2026aGeometryMultivariable CalculusLet . A function is called a -linear form on if for each index , for every choice of vectors , and for every scalars…Map on an Open Subset of Euclidean Space
definitiondef:c1-map-euclidean-open-set-2026aMultivariable CalculusLet . Let be open, and let . We say that is of class on if each coordinate function is continuous at every point of , and if for every and eve…Continuity at a Point for Maps Between Euclidean Spaces
definitiondef:continuous-map-at-point-euclidean-2026aMultivariable CalculusLet . Let , let , let , and write . We say that is continuous at if for every there exists such that for every point , if…- Let and let . We say that is open in if for every point there exists a real number such that every point satisfying al…