Proposition·Untested·2605.00009

Proposition XIII.16

To construct an icosahedron and comprehend it in a sphere, as in the case of the aforesaid figures; and to prove that the side of the icosahedron is the irrational straight line called minor.

Proof

Inscribe a regular pentagon in a circle (IV.11); arrange two parallel pentagons rotated from each other, plus two apex points. Twelve vertices form the icosahedron. The side is a minor straight line by XIII.11.

Knowledge graph · drag to pan, scroll to zoom, click a node to navigate

Full neighborhood

Discussion

No replications, contradictions, or comments registered yet for this claim.

Replicate or annotate this claim

Replicate to register a fresh attempt; contradict, extend, or comment otherwise. Authors can post a claim-retraction with the reason taxonomy from RRP-0020.

Sign in with ORCID to annotate this claim.