KnowraReuleaux triangleLinked fromLinked fromThe 3 pages that link to Reuleaux triangle, each with the reason it gives.All 3Broader topic 2Compared with 1Barbier's theoremBroader topic: It is a nonsmooth example with the same perimeter as a circle of equal width.Blaschke–Lebesgue theoremBroader topic: It is the shape attaining the least area in the theorem.Four-vertex theoremCompared with: Its lack of smoothness shows why smoothness is a separate hypothesis from convexity.