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Set existence is governed by explicit axioms and schemas.
DefinitionMathematics & logicCompleteness of the real numbersUpper-bounded nonempty real sets have least upper bounds.
Mathematical statementMathematics & logicFinite and countable setsCountability includes finite sets in this convention.
DefinitionMathematics & logicEquivalence relations and quotient classesAn equivalence relation partitions a set into classes.
DefinitionMathematics & logicModels, completeness and incompletenessSemantic consequence and arithmetic completeness are distinct.
Mathematical statementMathematics & logicInteger divisibility and the Euclidean algorithmRepeated division computes a greatest common divisor.
MethodMathematics & logicUnique prime factorization of integersPositive integers greater than one have unique prime factors.
Mathematical statementMathematics & logicInteger arithmetic modulo nCongruence identifies integers differing by a multiple of n.
DefinitionMathematics & logicChinese Remainder TheoremCoprime moduli specify one combined residue.
Mathematical statementMathematics & logicGroups and abelian groupsA group has associative composition, identity and inverses.
DefinitionMathematics & logicGroup homomorphisms and kernelsHomomorphisms preserve the group operation.
DefinitionMathematics & logicRings and identity conventionsA ring combines addition with distributive multiplication.
DefinitionMathematics & logicFields and divisionA field allows division by every nonzero element.
DefinitionMathematics & logicFundamental Theorem of AlgebraNonconstant complex polynomials factor into linear terms.
Mathematical statementMathematics & logicMetric spacesA metric supplies a distance satisfying three axioms.
DefinitionMathematics & logicTopological spacesA topology specifies which subsets are open.
DefinitionMathematics & logicCompactness and finite subcoversCompactness reduces every open cover to a finite one.
DefinitionMathematics & logicContinuity between topological spacesContinuity preserves openness through inverse images.
DefinitionMathematics & logicEuclidean and curved-surface geometryTriangle-angle relations depend on the geometry.
Mathematical statementMathematics & logicAbstract vector spacesVector-space laws extend beyond coordinate arrows.
DefinitionMathematics & logicBases and finite dimensionA basis spans without linear redundancy.
DefinitionMathematics & logicRank–nullity theoremKernel and image dimensions sum to domain dimension.
Mathematical statementMathematics & logicEigenvalues and eigenvectorsAn eigenvector changes only by a scalar factor.
DefinitionMathematics & logicFinite-dimensional self-adjoint spectral theoremSelf-adjoint operators have orthonormal eigenbases.
Mathematical statementMathematics & logicReal singular value decompositionAny real rectangular matrix has orthogonal factors.
Mathematical statementMathematics & logicConvergence and Cauchy sequencesReal convergence can be checked by distances between late terms.
Mathematical statementMathematics & logicInfinite series and absolute convergenceA series converges through its partial sums.
Mathematical statementMathematics & logicFinite Taylor approximation and remainderThe remainder quantifies a finite polynomial approximation.
Mathematical statementMathematics & logicUniform convergence of functionsOne cutoff controls the error at every domain point.
Mathematical statementMathematics & logicLebesgue integral and integrabilityIntegration starts from measurable simple functions.
Definition