# Geometría proyectiva: Obtaining conical shafts from two pairs Diameters Polar Conjugates

A conical axes are those conjugates polar diameters are orthogonal to each.

We recall that two polar conjugate diameters, necessarily pass through the center O of the conical, are the polar two points unfit (located at infinity) that they are conjugated, namely, the polar of each of these points contains the other.

These pairs of elements determine an involution of diameters (polar) Conjugates will be defined when two pairs of beams know and their homologues.

# Conical defined by the two foci and a point

One of the first problems we can solve based on the definition of conic as “locus of the centers of circumferences passing through a fixed point (focus) which are tangent to a circumference (focal circle centered the other focus)” It is the determination of the tapered from the two foci and a point.

The classic definition will be determined as the vertices A1 and A2 of the conical obtained.