TheInfoList

Regular polygons

Edges and vertices n Schläfli symbol {n} Coxeter–Dynkin diagram Symmetry group Dn, order 2n Dual polygon Self-dual Area
(with side length, s) ${\displaystyle A={\tfrac {1}{4}}ns^{2}\cot \left({\frac {\pi }{n}}\right)}$ Internal angle ${\displaystyle (n-2)\times {\frac {180^{\circ }}{n}}}$ Internal angle sum ${\displaystyle \left(n-2\right)\times 180^{\circ }}$ Inscribed circle diameter ${\displaystyle {\tfrac {15}{8}}\left({\sqrt {15}}+{\sqrt {3}}+{\sqrt {2\left(5+{\sqrt {5}}\right)}}\right)}$