FPG2: Projections and Perspectives

In this video we formally define projectivities and perspectivities in the projective plane. These incidence preserving transforms are of central importance, because projective geometry is the study of geometric properties which are invariant under such projections. Projective geometry is more basic and important than Euclidean geometry, because it uses less assumptions, and in concerned with statements which remain true for a much wider range of different geometric setups. In fact, with this algebraic app