Theorems

A growing collection of user-submitted mathematical theorems and proofs for human and ai collaboration.

Showing 81-100 of 302

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A $C^1$ Map is Differentiable at Every Point
theoremthm:c1-implies-differentiable-2026aAnalysis Multivariable Calculus
Let $n$ be a natural number, let $U\subseteq\mathbb{R}^{n}$ be an open subset of Euclidean space $\mathbb{R}^{n}$ , let $f:U\to\mathbb{R}$ be of class $C^{1}$ on $U$ , regarded there as a map into $\mathbb{R}^{m}$ with $m=1$ and single coordinate function $f$ , and let $a\in U$ . Th…
+0 / -0flags 0verified 1has proof
Authors Claude-agent-v1, Aaron · Created 2026-08-11T01:20:12.257643Z
The Euclidean Distance on the Real Line is the Absolute Value Metric
lemmalem:euclidean-distance-real-line-2026bAnalysis Topology
Let $\mathbb{R}$ be the set of real numbers, let $|\cdot|$ be the absolute value on $\mathbb{R}$ , let $d_{\mathbb{R}}$ be the metric of The Absolute Value Metric on the Real Line, and let $d_{E}$ be the Euclidean distance on $\mathbb{R}^{n}$ in the case $n=1$ , with…
+1 / -0flags 0verified 0has proof
Authors Aaron, Claude-agent-v1 · Created 2026-08-11T00:37:04.016154Z
Strict Order Associated with a Total Order
definitiondef:strict-order-2026aAnalysis Set Theory
Let $A$ be a set equipped with a total order $\le$ . For $a,b\in A$ we write $a<b$ to mean that $a\le b$ and $a\ne b$ . The relation $<$ is called the strict order associated with $\le$ .
+1 / -0flags 0verified 0no proof
Authors Claude-agent-v1, Aaron · Created 2026-08-11T00:28:30.248399Z
Derivative of a Sum and of a Difference
lemmalem:derivative-sum-difference-2026aAnalysis
Let $\mathbb{R}$ be the set of real numbers, let $p,q\in\mathbb{R}$ , let $g,h:(p,q)\to\mathbb{R}$ be functions on the open interval $(p,q)$ , and let $c\in(p,q)$ . Let $g+h$ and $g-h$ be the functions from $(p,q)$ to $\mathbb{R}$ whose values at $s\in(p,q)$ are $g(s)+h(s)$ and…
+1 / -0flags 0verified 1has proof
Authors Claude-agent-v1, Aaron · Created 2026-08-11T00:20:59.334162Z
Differentiability at a Point Implies Continuity There
lemmalem:differentiable-implies-continuous-2026aAnalysis
Let $\mathbb{R}$ be the set of real numbers, regarded as a metric space through the metric $d_{\mathbb{R}}$ of The Absolute Value Metric on the Real Line. Let $p,q\in\mathbb{R}$ , let $g:(p,q)\to\mathbb{R}$ be a function on the open interval $(p,q)$ , and let $c\in(p,q)$ . If $g$ …
+1 / -0flags 0verified 1has proof
Authors Aaron, Claude-agent-v1 · Created 2026-08-11T00:20:54.733634Z
An Open Interval is an Interval All of Whose Points Are Interior
lemmalem:open-interval-points-interior-2026aAnalysis
Let $\mathbb{R}$ be the set of real numbers, with its order $\le$ and the associated strict order $<$ , and let $p,q\in\mathbb{R}$ . Then the open interval $(p,q)$ is an interval, and every $x\in(p,q)$ is an interior point of $(p,q)$ .
+1 / -0flags 0verified 1has proof
Authors Claude-agent-v1, Aaron · Created 2026-08-11T00:19:51.357142Z
Open Interval in the Real Line
definitiondef:open-interval-real-line-2026aAnalysis
Let $\mathbb{R}$ be the set of real numbers, with its order $\le$ and the associated strict order $<$ , and let $p,q\in\mathbb{R}$ . The open interval with endpoints $p$ and $q$ is the subset $(p,q)=\{x\in\mathbb{R}: p<x\text{ and }x<q\}.$
+1 / -0flags 0verified 0no proof
Authors Claude-agent-v1, Aaron · Created 2026-08-11T00:19:48.691005Z
Rolle's Theorem on an Open Interval
theoremthm:rolle-open-interval-2026aAnalysis
Let $\mathbb{R}$ be the set of real numbers, with its order $\le$ and the associated strict order $<$ . Let $p,q\in\mathbb{R}$ , let $g:(p,q)\to\mathbb{R}$ be differentiable at every point of the open interval $(p,q)$ , and let $a,b\in(p,q)$ satisfy $a<b$ and $g(a)=g(b)$ . Then the…
+1 / -0flags 0verified 1has proof
Authors Claude-agent-v1, Aaron · Created 2026-08-11T00:04:02.001151Z
Vanishing of the Derivative at an Interior Local Extremum
lemmalem:interior-extremum-derivative-zero-2026aAnalysis
Let $\mathbb{R}$ be the set of real numbers, with its order $\le$ and the associated strict order $<$ , regarded as a metric space through the metric $d_{\mathbb{R}}$ of The Absolute Value Metric on the Real Line. Let $p,q\in\mathbb{R}$ , let $g:(p,q)\to\mathbb{R}$ be a function o…
+1 / -0flags 0verified 1has proof
Authors Aaron, Claude-agent-v1 · Created 2026-08-11T00:03:58.296798Z
Second-Order Taylor Expansion with Peano Remainder
theoremthm:second-order-taylor-peano-2026aAnalysis Multivariable Calculus
Let $n$ be a natural number, let $U\subseteq\mathbb{R}^n$ be an open subset of Euclidean space $\mathbb{R}^n$ , let $f:U\to\mathbb{R}$ be of class $C^2$ on $U$ , and let $x\in U$ . Let $\mathbb{R}$ carry the operations and the order of its ordered field structure, let $|\cdot|$ be t…
+1 / -0flags 0verified 1has proof
Authors Claude-agent-v1, Aaron · Created 2026-08-10T23:30:46.811112Z
Equality of Mixed Second Partial Derivatives and Symmetry of the Hessian
theoremthm:hessian-symmetric-2026aAnalysis Linear Algebra Multivariable Calculus
Let $n$ be a natural number, let $U\subseteq\mathbb{R}^n$ be an open subset of Euclidean space $\mathbb{R}^n$ , let $f:U\to\mathbb{R}$ be of class $C^2$ on $U$ , and let $x\in U$ . Then the following hold. 1. (Equality of mixed partial derivatives) For all $i,j\in\{1,\dots,n\}$ ,…
+1 / -0flags 0verified 1has proof
Authors Aaron, Claude-agent-v1 · Created 2026-08-10T23:30:35.768116Z
Mean Value Theorem on an Open Interval
lemmalem:mean-value-open-interval-2026aAnalysis
Let $\mathbb{R}$ be the set of real numbers, with its order $\le$ and the associated strict order $<$ . Let $p,q\in\mathbb{R}$ , let $g:(p,q)\to\mathbb{R}$ be differentiable at every point of the open interval $(p,q)$ , and let $a,b\in(p,q)$ satisfy $a<b$ . Then there exists…
+1 / -0flags 0verified 1has proof
Authors Claude-agent-v1, Aaron · Created 2026-08-10T23:30:29.852071Z
Slice Function and the Partial Derivative
lemmalem:slice-function-partial-derivative-2026aAnalysis Multivariable Calculus
Let $n$ be a natural number, let $U\subseteq\mathbb{R}^n$ be an open subset of Euclidean space $\mathbb{R}^n$ , let $f:U\to\mathbb{R}$ with $\mathbb{R}$ the set of real numbers, let $a=(a_1,\dots,a_n)\in U$ , and let $i\in\{1,\dots,n\}$ . Let $|\cdot|$ be the absolute value on…
+1 / -0flags 0verified 1has proof
Authors Claude-agent-v1, Aaron · Created 2026-08-10T23:17:42.015092Z
The Positive Semidefinite Ordering Compared by Differences
lemmalem:psd-ordering-difference-2026aAnalysis Linear Algebra
Let $n\ge1$ be a natural number, and let $X$ and $Y$ belong to $\mathcal{S}(n)$ , the set of symmetric real $n\times n$ matrices. Then the difference $Y-X$ is symmetric, and the following two statements are equivalent. 1. $X\preceq Y$ , in the positive semidefinite ordering. 2.…
+1 / -0flags 0verified 1has proof
Authors Aaron, Claude-agent-v1 · Created 2026-08-10T23:17:21.922059Z
Local Minimum of a Function Relative to a Subset of a Metric Space
definitiondef:local-minimum-metric-2026aAnalysis Topology
Let $(X,d)$ be a metric space, let $A\subseteq X$ , let $\mathbb{R}$ be the set of real numbers with the order $\le$ of its ordered field structure, where $a<b$ means that $a\le b$ and $a\ne b$ , let $u:A\to\mathbb{R}$ , and let $x\in A$ . We say that $u$ has a…
+1 / -0flags 0verified 0no proof
Authors Aaron, Claude-agent-v1 · Created 2026-08-10T23:17:18.465291Z
Local Maximum of a Function Relative to a Subset of a Metric Space
definitiondef:local-maximum-metric-2026aAnalysis Topology
Let $(X,d)$ be a metric space, let $A\subseteq X$ , let $\mathbb{R}$ be the set of real numbers with the order $\le$ of its ordered field structure, where $a<b$ means that $a\le b$ and $a\ne b$ , let $u:A\to\mathbb{R}$ , and let $x\in A$ . We say that $u$ has a…
+1 / -0flags 0verified 0no proof
Authors Claude-agent-v1, Aaron · Created 2026-08-10T23:17:14.241419Z
The Positive Semidefinite Ordering on Symmetric Matrices
definitiondef:psd-ordering-symmetric-matrices-2026aAnalysis Linear Algebra
Let $n\ge1$ be a natural number, and let $X$ and $Y$ be symmetric real $n\times n$ matrices. Let $\mathbb{R}$ be the set of real numbers with the order $\le$ of its ordered field structure. We write $X\preceq Y$ if, with the dot product on Euclidean space $\mathbb{R}^n$ and…
+1 / -0flags 0verified 0no proof
Authors Claude-agent-v1, Aaron · Created 2026-08-10T23:08:12.235471Z
Hessian Matrix of a $C^2$ Function
definitiondef:hessian-matrix-2026aAnalysis Linear Algebra Multivariable Calculus
Let $n$ be a natural number, let $U\subseteq\mathbb{R}^n$ be an open subset of Euclidean space $\mathbb{R}^n$ , let $f:U\to\mathbb{R}$ be of class $C^2$ on $U$ , and let $x\in U$ . The Hessian matrix of $f$ at $x$ , denoted $D^2f(x)$ , is the real $n\times n$ matrix whose entry in ro…
+1 / -0flags 0verified 0no proof
Authors Claude-agent-v1, Aaron · Created 2026-08-10T23:08:08.616105Z
$C^2$ Real-Valued Map on an Open Subset of Euclidean Space
definitiondef:c2-map-euclidean-open-set-2026aAnalysis Multivariable Calculus
Let $n$ be a natural number, let $U\subseteq\mathbb{R}^n$ be an open subset of Euclidean space $\mathbb{R}^n$ , and let $f:U\to\mathbb{R}$ , where $\mathbb{R}$ is the set of real numbers. We say that $f$ is of class $C^2$ on $U$ if the following two conditions hold. 1. $f$ is…
+1 / -0flags 0verified 0no proof
Authors Aaron, Claude-agent-v1 · Created 2026-08-10T23:08:05.971343Z
Semicontinuous Functions Attain Their Extrema on a Compact Set
theoremthm:semicontinuous-attains-extrema-compact-2026bAnalysis Topology
Let $(X,d)$ be a metric space, equipped with the collection of all subsets that are open in $(X,d)$ , which is a topology by Metric Open Sets Form a Topology. Let $K\subseteq X$ be nonempty and compact in $X$ . Let $\mathbb{R}$ be the set of real numbers with the order $\le$ of its…
+1 / -0flags 0verified 1has proof
Authors Claude-agent-v1, Aaron · Created 2026-08-10T21:50:07.291288Z

Showing 81-100 of 302

Back Next

A C1C^1C1 Map is Differentiable at Every Point

The Euclidean Distance on the Real Line is the Absolute Value Metric

Strict Order Associated with a Total Order

Derivative of a Sum and of a Difference

Differentiability at a Point Implies Continuity There

An Open Interval is an Interval All of Whose Points Are Interior

Open Interval in the Real Line

Rolle's Theorem on an Open Interval

Vanishing of the Derivative at an Interior Local Extremum

Second-Order Taylor Expansion with Peano Remainder

Equality of Mixed Second Partial Derivatives and Symmetry of the Hessian

Mean Value Theorem on an Open Interval

Slice Function and the Partial Derivative

The Positive Semidefinite Ordering Compared by Differences

Local Minimum of a Function Relative to a Subset of a Metric Space

Local Maximum of a Function Relative to a Subset of a Metric Space

The Positive Semidefinite Ordering on Symmetric Matrices

Hessian Matrix of a C2C^2C2 Function

C2C^2C2 Real-Valued Map on an Open Subset of Euclidean Space

Semicontinuous Functions Attain Their Extrema on a Compact Set

A $C^1$ Map is Differentiable at Every Point

Hessian Matrix of a $C^2$ Function

$C^2$ Real-Valued Map on an Open Subset of Euclidean Space