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.
Evaluation at four distinct real points gives an inner product on polynomials of degree at most three
Example
On the real vector space of polynomials of degree at most , evaluation at four distinct real points defines an inner product by
For example, the points may be .
Facts & Assumptions
Given: Four distinct real scalars and polynomials .
An inner product is a symmetric bilinear form whose diagonal is nonnegative and vanishes only at zero (Real and complex inner product spaces, with the inner product linear in the first argument).
A nonzero polynomial over a domain has at most as many distinct roots as its degree (A nonzero polynomial of degree over an integral domain has at most distinct roots).
Finite sums are compatible with the additive and multiplicative laws of the scalar field (The product of a finite list in a monoid, by recursion, with the empty product () equal to the identity).
Verification
By [L3], the displayed formula is bilinear and symmetric. Also .
If , every real square in the sum is zero, so for four distinct . If were nonzero, [L2] would give at most three roots because . Thus , proving definiteness and hence [L1].
Depends on
- Real and complex inner product spaces, with the inner product linear in the first argument
- The product $g_0 g_1 \cdots g_{n-1}$ of a finite list in a monoid, by recursion, with the empty product ($n = 0$) equal to the identity
- A nonzero polynomial of degree $n$ over an integral domain has at most $n$ distinct roots
Used by
Nothing in the library uses this result yet.
Dependency tree · next 3 levels
Direct dependencies and their dependencies through the next three levels: 43 results over 13 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.