Dihedral Kaleidoscopes

Uses mirrors at varying angles and colored geometric reflections to illustrate principles of symmetry operations. Illustrates that mirror angles of pi over 2, pi over 3, and pi over 4 produce dihedral groups of order 4, 6, and 8 respectively and points out rotational subgroups. Shows how, if three mirrors with dihedral angles of pi over 3 are set perpendicular to a plane, a true kaleidoscope is formed by each pair of angles. Concludes with a series of colored illustrations of tessellation.