Pascal's Theorem
If a hexagon ABCDEF is inscribed in a conic, then opposite sides intersect
in three pointsP,Q,R (resp AB.DE, BC.EF, CD.FA) which are collinear.
This theorem was discovered by B.Pascal (1623-1662)
when he was sixteen.
Note that Pascal's theorem is true regardless
of where the points lie on the conic. The
figure below shows a very non-convex hexagon.
Let's Drag C(C,A,E) to Transform below curve into
ellipse.
controller
| Backward step | Forward step | { | Figure drag | Choice of trace | Animation spring | Downloard of figure |
with cabri Java