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Distribution-free procedures still require assumptions.
MethodPhysics · Mathematics & logicEuler–Lagrange equationsStationary action supplies coordinate equations of motion.
Mathematical statementPhysics · Mathematics & logicHamilton's canonical equationsCanonical coordinates and momenta evolve from the Hamiltonian.
Mathematical statementPhysics · Mathematics & logicWave superposition and interferenceLinear disturbances add; their relative phase determines reinforcement.
ModelPhysics · Mathematics & logicGeodesic motionFree test motion follows the metric connection.
ModelMeasurement · Mathematics & logicCovariance in uncertainty modelsShared input variation belongs in the joint uncertainty description.
MethodMathematics & logicIntermediate values and compact-domain extremaA continuous real function on a closed bounded interval attains a maximum and minimum and takes every value between its endpoint values.
Mathematical statementMathematics & logicProduct, quotient and chain rulesDifferentiable real functions satisfy (fg)′=f′g+fg′ and (g∘f)′=(g′∘f)f′.
Mathematical statementMathematics & logicMean value theoremIf f is continuous on [a,b] and differentiable on (a,b), a<b, some c∈(a,b) satisfies f′(c)=(f(b)−f(a))/(b−a).
Mathematical statementMathematics & logicDarboux intermediate-value property of derivativesFor f differentiable throughout an open real interval, its derivative takes every value strictly between f′(a) and f′(b) at some c∈(a,b), whenever a<b are points of that interval.
Mathematical statementMathematics & logicSubstitution in a definite integralFor g of class C¹ on [a,b] and f continuous on an interval containing g([a,b]), ∫ₐᵇ f(g(x))g′(x)dx=∫g(a)ᵍ(b)f(u)du.
MethodMathematics & logicIntegration by partsFor u,v of class C¹ on [a,b], ∫ₐᵇuv′dx=[uv]ₐᵇ−∫ₐᵇu′v dx.
MethodMathematics & logicDarboux sums and Riemann integrabilityFor bounded real f on [a,b], lower and upper Darboux sums use each subinterval's infimum and supremum.
Mathematical statementMathematics & logicContinuity and the Riemann integrability criterionA bounded real function on [a,b] is Riemann integrable exactly when its discontinuity set has Lebesgue measure zero.
Mathematical statementMathematics & logicWeierstrass M-testIf real functions fₙ on one set A satisfy |fₙ(x)|≤Mₙ for all x∈A, with Mₙ≥0 and ΣMₙ<∞, then Σfₙ converges uniformly and absolutely on A.
Mathematical statementMathematics & logicImproper integrals and independent endpoint limitsAn improper integral is the finite limit of proper integrals as a singular endpoint or an infinite endpoint is approached.
DefinitionMathematics & logicIntegral test and p-seriesFor positive continuous decreasing f on [1,∞), Σₙ₌₁∞f(n) and ∫₁∞f(x)dx converge or diverge together.
Mathematical statementMathematics & logicAlternating-series convergence and remainderIf bₙ≥0 decreases to zero, Σ(−1)ⁿbₙ converges; the absolute error after N terms is at most the next omitted magnitude b_(N+1).
Mathematical statementMathematics & logicMonotone convergence and Fatou's lemmaFor increasing nonnegative measurable fₙ→f, ∫fₙdμ→∫f dμ.
Mathematical statementMathematics & logicDominated convergence theoremIf measurable real fₙ→f pointwise and |fₙ|≤g for one integrable g, then ∫fₙdμ→∫f dμ.
Mathematical statementMathematics & logicSubgroups and the subgroup testA subgroup H⊆G is a group under G's restricted operation.
DefinitionMathematics & logicCosets and subgroup indexLeft cosets gH={gh:h∈H} partition G.
DefinitionMathematics & logicNormal subgroups and quotient groupsA subgroup N is normal when gNg⁻¹=N for every g∈G.
Mathematical statementMathematics & logicIdeals and quotient ringsA two-sided ideal I of R is an additive subgroup absorbing multiplication by R on either side.
DefinitionMathematics & logicHolomorphic functions and Cauchy–Riemann equationsA function is holomorphic on an open set when it is complex differentiable at every point.
DefinitionMathematics & logicComplex contour integration and Cauchy's theoremFor a piecewise C¹ path γ, ∫γf(z)dz=∫f(γ(t))γ′(t)dt.
Mathematical statementMathematics & logicCauchy integral formula and derivativesIf f is holomorphic on a neighborhood of a closed disk and z lies inside its positively oriented boundary γ, f⁽ⁿ⁾(z)=n!/(2πi)∮γ f(w)/(w−z)ⁿ⁺¹dw for n≥0.
Mathematical statementMathematics & logicComplex Taylor and Laurent expansionsA holomorphic function has a convergent Taylor expansion within a disk free of singularities.
Mathematical statementMathematics & logicResidues and the residue theoremThe residue at an isolated singularity is the (z−a)⁻¹ coefficient of its Laurent series.
Mathematical statementMathematics & logicFloating-point numbers and roundoffFloating-point numbers use a sign, finite significand and exponent.
Approximation