# Reflection symmetry (2D)

(Redirected from A1×I)

Reflection symmetry (2D) | |
---|---|

Rank | 2 |

Space | Spherical |

Order | 2 |

**Two-dimensional reflection symmetry**, also known as **dyadic symmetry** and notated as **A _{1}×I**, is a 2D spherical symmetry group. It is the symmetry group of the isosceles triangle and corresponds to mirror symmetry. It has only one reflectional element. Every regular polygonal symmetry has this as a subsymmetry, and it is the symmetry of any bilaterally-symmetric polygon.

### Subgroups[edit | edit source]

- Identity symmetry (maximal)