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Mathematics

Group Theory and Symmetries of Geometric Objects

Quick fact

The symmetries of a regular n-gon form a group of exactly 2n transformations, combining rotations and reflections, known as the dihedral group Dₙ.

Why this is interesting

You've probably noticed that a square can be rotated 90° and still look the same—but have you ever wondered what all the ways to move it that leave it unchanged are?