How statement and proof provenance work
The first chip identifies the source of the statement or construction; the second identifies the source of its local proof or verification.
- Literature-sourced: the exact statement appears in a cited source; only wording and notation differ.
- AI-adapted: a semantically identical restatement of literature-sourced material, modulo indexing, notation, and boundary cases adopted by the library.
- AI-generated: a genuinely novel statement formulated by AI, with no source for the claim itself.
These labels describe origin, not correctness: citations and verification chips remain separate evidence.
The exponential function is strictly increasing
Statement
The exponential function is continuous and strictly increasing on .
Facts & Assumptions
Given: The exponential function.
Its derivative equals itself (The exponential function is smooth and ) and it is everywhere positive (The exponential is positive and satisfies ).
The mean value theorem applies to a continuous function on a closed interval and converts a positive interior derivative into strict increase (The mean value theorem, as the case of Cauchy's: for continuous on with and differentiable on there is with ). A power-series sum is continuous at every point strictly inside its convergence interval, and the exponential series has infinite radius (The sum of a real power series is continuous at every point strictly inside its interval of convergence, The exponential series converges absolutely for every real argument).
Proof
If , the mean value theorem gives for some .
Both factors on the right are positive, so . Continuity is the cited power-series conclusion.
Depends on
- The exponential series converges absolutely for every real argument
- The exponential function is smooth and $(\exp)'=\exp$
- The exponential is positive and satisfies $\exp(-x)=1/\exp(x)$
- The mean value theorem, as the case $g(x) = x$ of Cauchy's: for $f$ continuous on $[a,b]$ with $a < b$ and differentiable on $(a,b)$ there is $c \in (a,b)$ with $f(b) - f(a) = f'(c)(b-a)$
- The sum of a real power series is continuous at every point strictly inside its interval of convergence
Used by
- Finite-class empirical-risk selection with exponential weights Algorithm
- A sample-size consequence for compression schemes Corollary
- Compatible extensions from the finite simple core Corollary
- Lyapunov central limit theorem Corollary
- Polynomial and exponential minimax estimation rates Corollary
- Positive-degree Dolbeault vanishing on pseudoconvex domains Corollary
- The exponential is a continuous bijection from ℝ onto (0,∞) Corollary
- A boundary mode has a different concentration rate Counterexample
- A bounded continuous normalized function that is not of positive type Counterexample
- A discontinuous positive solution of F(x+y)=F(x)F(y) Counterexample
- A generalized Bayes credible set can have zero coverage Counterexample
- A nonintegrable error envelope destroys the linear Hellinger rate Counterexample
- A singular interior mode need not have Gaussian scaling Counterexample
- Assuming choice, a Hamel-basis additive map transported through exp gives a discontinuous logarithmic function that is not c log Counterexample
- f(x+iy)=eˣ(cos 2y+i sin 2y) is continuous, satisfies f(z+w)=f(z)f(w) and f(1)=e, but is not the standard complex exponential Counterexample
- Feller negligibility cannot be removed from the converse Counterexample
- Omitting the second-stage correction destroys cubic local accuracy Counterexample
- Point evaluation is unbounded below the Sobolev continuity threshold Counterexample
- The exponential is not uniformly continuous on ℝ Counterexample
- Two closed convex sets can have no strong separator Counterexample
- Diagonal Dirichlet sine-mode heat model with constant forcing Definition
- Generalized Bayes loss update and temperature Definition
- Kullback–Leibler divergence Definition
- Misfit evidence and the potential posterior law Definition
- Sub-Gaussian variables and vectors, and sub-exponential variables Definition
- The Jacobi theta function θ(t)=∑_n∈ℤ e^-π n² t for t>0 Definition
- The six hyperbolic functions and their natural domains Definition
- A Dirac mass has precisely sufficiently negative Sobolev order Example
- A family containing K₁ is viral for vacuous reasons Example
- A finite identifiable model with posterior consistency Example
- A finite-mean polynomial-tail reward is not sub-Gaussian Example
- A Gaussian harmonic leapfrog resonance Example
- A globally Lipschitz Hamiltonian force Example
- A mixture of straight Gaussian paths has a nonlinear marginal velocity Example
- A parameter ledger for the high-girth, high-chromatic alteration proof Example
- A positive mode multiplier too small to certify Example
- A positive non-log-convex solution of the Gamma functional equation Example
- A stable coupled model has an unstable explicit fast microstep Example
- A stiff penalty equation defeats a fixed explicit step Example
- A strictly plurisubharmonic exhaustion of the convex unit ball Example
…and 143 more results.
Dependency tree · two levels
25 results within two dependency steps of this one, each drawn at its shortest distance from it. An arrow runs from a result to what uses it, so the chart reads left to right and ends at this result, which carries a heavier outline. Every node is a link to that result. Click elsewhere on the chart to enlarge it.
Sources
- MIT OpenCourseWare 18.100B Real Analysis, Spring 2025 full lecture notes (standard reference, not scraped)
- J. Lebl, Basic Analysis, Logarithm and Exponential (standard reference, not scraped)