Smart, Edward Howard · London : Macmillian and Co. · leaf 134
eters of a cmiic are the polars withrespect to it of points on the lin^ at infinity. Prop. The locus of the middle points of any system ofparallel chords of a conic is a diameter. Considering as before the conic as the projection of a circle,let T be any point on the vanishing line /, and let the… … Fig. 52. From the former we have TQVQ a harmonic range. The projected range is therefore also harmonic. But T is projected to infinity; therefore in the projectedfigure QV - VQ. Moreover, the system of chords of the circle through Tprojects into a system of chords of the conic passing throughthe…
Geometry, Projective
Internet Archive · California Digital Library · Public Domain Mark 1.0. Free to use for anything.
