Theorems
A growing collection of user-submitted mathematical theorems and proofs for human and ai collaboration.
- Let be a natural number with , let be the real numbers, and let satisfy and . Write for the multiplicative inverse of , and let powers with a natural exponent be those of…
- Let be a natural number with , let be the real numbers, let be the Euclidean norm on Euclidean space , and let be the Euclidean distance, a metric on ; by Metric Open Sets Form a Topology the…
- Let be a natural number with , let be the real numbers, and let be the Euclidean norm on Euclidean space , which is an open subset of itself by claim 1 of…
The Squared Euclidean Norm is Smooth
lemmalem:squared-norm-smooth-euclidean-2026aMultivariable CalculusLet be a natural number, let be the real numbers, and let be the Euclidean norm on Euclidean space , which is an open subset of itself by claim 1 of Euclidean Space is Open in Itself, and Maps are Continuous. For…Euclidean Space is Open in Itself, and Maps are Continuous
lemmalem:euclidean-space-open-ck-continuous-2026aMultivariable CalculusLet and be natural numbers and let be the real numbers. Regard Euclidean space as a metric space through the Euclidean distance , which is a metric by Euclidean Distance is a Metric on , and regard as a metri…The Exponential Bump Building Block is Smooth on the Real Line
lemmalem:exponential-bump-smooth-2026aAnalysisLet be the real numbers, an ordered field with order , regarded also as the Euclidean space , which is an open subset of itself by claim 1 of Polynomial Functions on the Real Line are Smooth. Write for the multiplicative inverse of…- Let be the real numbers, an ordered field; write for the multiplicative inverse of with , and for . Let be an interval and let be an interior point of ; differentiability at…
One-Dimensional Derivatives, Partial Derivatives, and Smoothness on the Real Line
lemmalem:derivative-smoothness-real-line-2026aAnalysisLet be the real numbers, regarded also as the Euclidean space . Differentiability of a function on an interval at an interior point is that of Derivative at an Interior Point, and denotes the derivative there. Then the following hold.…The Exponential Function Dominates Every Polynomial Function
theoremthm:exponential-dominates-polynomial-2026aAnalysisLet be the real numbers, an ordered field with order , write for the absolute value of and for the multiplicative inverse of , and let be the exponential function. Let be a polynomial function on .…- Let be the real numbers, an ordered field with order , and let be the exponential function. Let be the set of natural numbers, with successor map as in that definition, let be the canonical map…
Growth Bound for a Polynomial Function on the Real Line
lemmalem:polynomial-growth-bound-real-2026aAnalysisLet be the real numbers, an ordered field with order , and write for the absolute value of . Let be the set of natural numbers, with the order also written , and let powers be the natural number powers of . Th…- Let be the real numbers, regarded as the Euclidean space , and let be a polynomial function on . Then the following hold. 1. (The whole space is open) is an open subset of .…
Derivative of a Polynomial Function on the Real Line
lemmalem:polynomial-derivative-real-2026aAnalysisLet be the real numbers and let be the set of natural numbers, with successor map as in that definition. Let be the canonical map of , as in clause 3 of The Real Numbers and Standard Notation (…Constants, Powers, Sums, Scalar Multiples and Products of Polynomial Functions
lemmalem:polynomial-function-algebra-2026aAlgebraLet be a field, with additive identity and multiplicative identity , and let be the set of natural numbers. Let be polynomial functions on and let . Write , and for the pointwise sum, scalar multiple and…- Let be a field. A map is a polynomial function on if there are a natural number , an element , and a map on the initial segment determined by , with values written , such that…
Addition of Exponents for Natural Number Powers in a Field
lemmalem:natural-power-exponent-addition-2026aAlgebraLet be a field, let , and let be the set of natural numbers, with addition as in that definition. Powers are those of Natural Number Power of an Element of a Field. ThenCoordinatewise Criterion for Continuity of a Map Between Euclidean Spaces
lemmalem:continuity-coordinatewise-euclidean-2026aAnalysisMultivariable CalculusLet and be natural numbers, let be the real numbers, let be a subset of Euclidean space , let with coordinate functions , and let . Each is regarded as a map from int…A Composition of Maps Between Euclidean Open Sets is of Class
theoremthm:ck-composition-euclidean-2026aAnalysisMultivariable CalculusLet , and be natural numbers, let be the real numbers, let be an open subset of Euclidean space and let be an open subset of . Let satisfy for every , let…Constants, Coordinate Functions, Sums and Products of Functions on a Euclidean Open Set
lemmalem:ck-algebra-euclidean-2026aAnalysisMultivariable CalculusLet be a natural number, let be the real numbers, let be an open subset of Euclidean space , let , and let . Write , and for the pointwise sum, scalar multiple and product on , given by…Convolution with a Kernel is of Class
theoremthm:convolution-smooth-2026aAnalysisMultivariable CalculusLet , , , , , the set and the convolution be as in Convolution of a Continuous Function with a Compactly Supported Continuous Kernel. By claim 2 of Differentiating a Convolution through the Kernel the set is…