Definition:Symmetry Group of Line Segment

Group Example
Let $\triangle AB$ be a line segment.


 * SymmetryGroupLineSegment.png

The symmetry mappings of $AB$ are:
 * The identity mapping $e$
 * The rotation $r$ of $180 \degrees$ about the midpoint of $AB$.

This group is known as the symmetry group of the line segment.

Group Presentation
Its group presentation is:

Also see

 * Symmetry Group of Line Segment is Group
 * Symmetry Group of Line Segment is Symmetric Group