Math 2.0

Statements

A theorem, a lemma, a proposition, a corollary, a fact or an axiom.

Ideas 901–1050 of 1926.

NameKindSubject
Degree of a productPropositionCommutative algebra
Power series of arctangentTheoremFunctions of a complex variable
The cross product is perpendicular to its factorsPropositionLinear and multilinear algebra; matrix theory
First Borel–Cantelli lemmaLemmaProbability theory and stochastic processes
Cauchy–Riemann equationsTheoremFunctions of a complex variable
Integration in polar coordinatesTheoremReal functions
The characteristic function determines the distributionTheoremProbability theory and stochastic processes
Existence of finite fields of every prime power orderTheoremField theory and polynomials
Axiom of extensionalityAxiomMathematical logic and foundations
The successor function is injectiveAxiomMathematical logic and foundations
Dirac's theorem on Hamiltonian cyclesTheoremCombinatorics
C^k function characterised by continuous derivativesPropositionReal functions
Product of the gcd and the lcmPropositionNumber theory
Remainder theoremTheoremCommutative algebra
Reduction of a higher-order equation to a first-order systemPropositionOrdinary differential equations
Third isomorphism theoremTheoremGroup theory and generalizations
Term-by-term differentiationTheoremSequences, series, summability
Bounded derivative on a convex set implies LipschitzCorollaryReal functions
An algebraic extension of an algebraic extension is algebraicTheoremField theory and polynomials
Product of a subgroup and a normal subgroup is a subgroupPropositionGroup theory and generalizations
Characteristic polynomial does not depend on the basisPropositionLinear and multilinear algebra; matrix theory
Surjective iff it has a right inversePropositionMathematical logic and foundations
Row rank equals column rankTheoremLinear and multilinear algebra; matrix theory
Variance of a sum of independent random variablesTheoremProbability theory and stochastic processes
Sign of a cyclePropositionGroup theory and generalizations
Frobenius coin problemTheoremNumber theory
Derivative of cosineTheoremSpecial functions
Intersection of subspacesPropositionLinear and multilinear algebra; matrix theory
Continuous real function on a compact set attains its boundsTheoremGeneral topology
Fibonacci numbers as sums of binomial coefficientsTheoremNumber theory
Subgroups of index two are normalPropositionGroup theory and generalizations
Logarithm of a powerCorollarySpecial functions
First Sylow theoremTheoremGroup theory and generalizations
Product ruleTheoremReal functions
Dirichlet's testTheoremSequences, series, summability
Multiplicativity of the Möbius functionPropositionNumber theory
Kummer's theoremTheoremNumber theory
Euler's theoremTheoremNumber theory
Morera's theoremTheoremFunctions of a complex variable
Volume of a boxPropositionMeasure and integration
Every polynomial has a root in some extension fieldTheoremField theory and polynomials
Product of continuous functions is continuousPropositionReal functions
Continuity is equivalent to sequential continuity in metric spacesTheoremGeneral topology
Abel's identityTheoremOrdinary differential equations
Subsequences of a convergent sequence converge to the same limitPropositionSequences, series, summability
Finite-dimensional spaces are isomorphic iff they have equal dimensionTheoremLinear and multilinear algebra; matrix theory
De Morgan's laws for setsTheoremMathematical logic and foundations
Size of a conjugacy class is the index of the centraliserPropositionGroup theory and generalizations
Banach fixed point theoremTheoremOperator theory
Lagrange multipliersTheoremOperations research, mathematical programming
Cartan–Dieudonné theoremTheoremGeometry
If 2^n + 1 is prime then n is a power of 2PropositionNumber theory
Polynomials of degree two or three are irreducible iff they have no rootsPropositionField theory and polynomials
Pythagorean theoremTheoremGeometry
Rule of productTheoremCombinatorics
A tree on n vertices has n − 1 edgesTheoremCombinatorics
Cancellation lawsPropositionGroup theory and generalizations
Minimal polynomial divides every annihilating polynomialPropositionLinear and multilinear algebra; matrix theory
Order of a powerPropositionGroup theory and generalizations
Term testPropositionSequences, series, summability
Euler lineTheoremGeometry
Gradient is orthogonal to level setsPropositionReal functions
Bézout's identity in a Euclidean domainTheoremCommutative algebra
Compact closed unit ball implies finite dimensionTheoremFunctional analysis
Continuous functions on a closed bounded interval are uniformly continuousTheoremReal functions
Euler's formula for planar graphsTheoremCombinatorics
Line integral as an integral over the parameter intervalTheoremReal functions
Complete subspaces are closedPropositionGeneral topology
Rank–nullity theoremTheoremLinear and multilinear algebra; matrix theory
Irrationality of eTheoremNumber theory
Law of total probability for an event and its complementCorollaryProbability theory and stochastic processes
Epsilon-delta definition of continuityPropositionReal functions
Chinese remainder theorem for ringsTheoremCommutative algebra
Time translation of solutions of an autonomous systemPropositionOrdinary differential equations
Trace of a linear map is the trace of its matrixPropositionLinear and multilinear algebra; matrix theory
R/M is a field iff M is maximalTheoremCommutative algebra
Euclid–Euler theoremTheoremNumber theory
Sylvester's law of inertiaTheoremLinear and multilinear algebra; matrix theory
Newton's identitiesTheoremCombinatorics
A subspace of full dimension is the whole spacePropositionLinear and multilinear algebra; matrix theory
There is a natural number n with 1/n below any positive epsilonCorollaryReal functions
Taylor's theorem with the integral remainderTheoremApproximations and expansions
Dimension theorem for vector spacesTheoremLinear and multilinear algebra; matrix theory
Sylvester's criterionTheoremLinear and multilinear algebra; matrix theory
Cholesky decompositionTheoremLinear and multilinear algebra; matrix theory
Product of exponentialsTheoremSpecial functions
Volume of a ball in R^3PropositionReal functions
A prime is a Gaussian prime if and only if it is 3 modulo 4TheoremNumber theory
Hoeffding's inequalityTheoremProbability theory and stochastic processes
Moment-generating function of a sum of independent random variablesPropositionProbability theory and stochastic processes
Extreme value theoremTheoremReal functions
Cantor's theoremTheoremMathematical logic and foundations
Gram–Schmidt vectors are orthogonalPropositionLinear and multilinear algebra; matrix theory
A monotone function has countably many discontinuitiesTheoremReal functions
Number of injectionsTheoremCombinatorics
Hall's theorem for bipartite graphsTheoremCombinatorics
Countable intersection of dense open sets is densePropositionGeneral topology
The exterior derivative squares to zeroTheoremGlobal analysis, analysis on manifolds
Tietze extension theoremTheoremGeneral topology
Impossibility of squaring the circleTheoremField theory and polynomials
Continuity of probability measuresPropositionProbability theory and stochastic processes
Uniform limit theoremTheoremSequences, series, summability
Handshaking lemmaTheoremCombinatorics
Wallis productTheoremNumber theory
Number of elements of each order in a cyclic groupTheoremGroup theory and generalizations
Monotonicity of the cumulative distribution functionPropositionProbability theory and stochastic processes
Multinomial theoremTheoremCombinatorics
Euler's partition theoremTheoremCombinatorics
Decomposition of a permutation into transpositionsTheoremGroup theory and generalizations
Poisson limit theoremTheoremProbability theory and stochastic processes
Squeeze theoremTheoremSequences, series, summability
Dini's theoremTheoremSequences, series, summability
Eisenstein's lemmaLemmaNumber theory
The principal logarithm is holomorphic off the branch cutPropositionSpecial functions
A root of an integer is an integer or irrationalTheoremNumber theory
Second fundamental theorem of calculusTheoremReal functions
De Morgan's laws in a Boolean algebraPropositionOrder, lattices, ordered algebraic structures
Absolutely convergent series convergeTheoremSequences, series, summability
Catalan recurrenceTheoremCombinatorics
Gauss–Wantzel theoremTheoremField theory and polynomials
The order modulo p divides p − 1CorollaryNumber theory
Trace of a product is symmetricPropositionLinear and multilinear algebra; matrix theory
Brooks' theoremTheoremCombinatorics
Fermat's Last TheoremTheoremNumber theory
Tail sum formula for expectationPropositionProbability theory and stochastic processes
Existence of an orthonormal basisTheoremLinear and multilinear algebra; matrix theory
Distinct eigenvalues imply diagonalisableCorollaryLinear and multilinear algebra; matrix theory
Binary trees are counted by Catalan numbersTheoremCombinatorics
Comparability of cardinalsTheoremMathematical logic and foundations
Identity theoremTheoremFunctions of a complex variable
Term-by-term integrationTheoremSequences, series, summability
Matrix exponential as the solution of a linear systemTheoremOrdinary differential equations
Universal property of the tensor productTheoremLinear and multilinear algebra; matrix theory
Continuity via open setsTheoremGeneral topology
Sum of independent Poisson random variablesPropositionProbability theory and stochastic processes
Irrationality of the square root of a primeTheoremNumber theory
Hilbert's basis theoremTheoremCommutative algebra
Existence of nth roots of complex numbersTheoremField theory and polynomials
Power series are holomorphic in the disc of convergenceTheoremFunctions of a complex variable
Fundamental theorem of contour integrationTheoremFunctions of a complex variable
Intersecting chords theoremTheoremGeometry
Pascal's ruleTheoremCombinatorics
Closed balls are closedPropositionGeneral topology
Homotopy invariance of line integrals of closed formsTheoremReal functions
Decomposition of a permutation into disjoint cyclesTheoremGroup theory and generalizations
Quadratic reciprocity for the Jacobi symbolTheoremNumber theory
Mercator seriesTheoremFunctions of a complex variable
Power series of complex cosinePropositionSpecial functions
Diagonalisation of a quadratic formTheoremNumber theory
Decomposition into generalised eigenspacesTheoremLinear and multilinear algebra; matrix theory