Alphabeta Math
DefinitionDefinition: AI-adaptedProof: Not applicableSession-authored (Fable 5 assisted)audited 2026-08-02
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.

Sine and cosine defined by their real power series

Definition

For xRx\in\mathbb R, define sinx:=n=0(1)nx2n+1(2n+1)!,cosx:=n=0(1)nx2n(2n)!.\sin x:=\sum_{n=0}^{\infty}\frac{(-1)^nx^{2n+1}}{(2n+1)!},\qquad\cos x:=\sum_{n=0}^{\infty}\frac{(-1)^nx^{2n}}{(2n)!}.

These are real power series in the sense of A real power series about a centre, its interval of convergence, and its radius in [0,+][0,+\infty]. Their convergence for every real argument is discharged by The sine and cosine power series converge absolutely for every real argument .

Depends on

Used by

Dependency tree · next 3 levels

Direct dependencies and their dependencies through the next three levels: 34 results over 9 levels. An arrow runs from a result to what uses it, and this result sits at the bottom with a heavier outline. Click the chart to enlarge it.

Sources