In geometry, a point reflection or inversion in a point (or inversion through a point, or central inversion) is a type of isometry of Euclidean space. An object that is invariant under a point reflection is said to possess point symmetry; if it is invariant under point reflection through its center, it is said to possess central symmetry or to be centrally symmetric.
Point reflection can be classified as an affine transformation. Namely, it is an isometric involutive affine transformation, which has exactly one fixed point, which is the point of inversion. It is equivalent to a homothetic transformation with scale factor equal to -1. The point of inversion is also called homothetic center.
Read more about Point Reflection: Terminology, Examples, Formula, Point Reflection As A Special Case of Uniform Scaling or Homothety, Point Reflection Group, Point Reflections in Mathematics, Properties, Inversion With Respect To The Origin, See Also
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