Projectivities
- Author:
- GeoGebra Materials Team
Definitions:
A Range is the set of all points on a line.
A Pencil is the set of all lines through a points.
Ranges and Pencils are one-dimensional forms.
The Range is a section (by the line) of the pencil.
The Pencil projects the range (from the point).
The Range A is a section (by line c) of the pencil a.
The Pencil a projects the range (A) from point C.
The Range H, I, J is a section (by the line a) of the pencil h, i, j
The pencil h, i, and j projects the range (H, I, J) from point A