Free public beta until December 4, 2026: every course is open, no card needed. After that, the first chapter of each course stays free and full access is a one-time $39 ($19 for up to 100 founding members chosen for helpful feedback). Your progress is kept. How the beta works

dihedral group

The group of all $2n$ symmetries of a regular $n$ -gon -- $n$ rotations and $n$ reflections -- under composition.

Loading interactive…

Examples

$D_4$ : the 8 symmetries of a square, 4 rotations and 4 reflections.