Perfect Shape and Isoperimetric Problem

You have probably heard of Dido's problem — a classic example of the calculus of variations. But is there a synthetic geometric solution? Yes, and it was invented by Jakob Steiner

CONTENT
0:00 - Prelude
0:37 – Symmetry helps
1:26 - Back to antiquity
2:01 – Bulge idea
3:11 — Unequal parts?
4:12 —The hardest puzzle ever!
5:30 — Dido's problem solution
6:06 — Is there a mistake?
6:57 — Answer to the first problem
7:18 — Isoperimetric inequality
8:04 — Final chord

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