How support lines touch an arc
arXiv:1907.10215 · doi:10.13140/RG.2.2.12818.20167
Abstract
We prove that each simple polygonal arc γ attains at most two pairs of support lines of given angle difference such that each pair has s1 < s2 < s3 that γ(s1) and γ(s3) are on one such line and γ(s2) is on the other line.
unpublished note 2013