Special cubics and quartics produced by projective pencils of straight lines and conics (1916)
Marshall, Robert Haskell · leaf 34
m the fact that itpasses through the base points of the pencil of circles whichalso pass through the circular points. The cubic also passesthrough these, and is therefore circular. According to a theorem in Part I a circular cubic may begei.erated in an infinite number of ways by projective… … 14- (xVy-2aCx -£f3 y)y -yVxf E^xy f-;i(3 y^ 0 .Now xV 2c(xy-i-y(2(3-1) may be resolved into the tw) linearfactors /^x + (o^-^/<:^-2(3-l)y//x-h («^-/oCVl - 2(3 ) y] ,so that the cubic appears now as the product of the two pro-jective pencils xVy-;.2o( X- 2 ^ y-hA^--)y] x-hio^ - A -2(3+l)y-Ay…
