Revision as of 08:28, 13 July 2022 edit 178.3.217.60 (talk) →Cross product was wrong, now it is: (x,y,1)\times (x',y',0) = (-y',x',xy'-yx') ← Previous edit		Revision as of 10:46, 13 July 2022 edit undo 178.3.217.60 (talk) →corrected dual of dual because of corrected cross product Next edit →
Line 35: The dual of an [[inflection point]] will give a [[Cusp (singularity)\|cusp]] and two points sharing the same tangent line will give a self-intersection point on the dual. From the projective description, one may compute the dual of the dual:<blockquote><math>(x(y'x'y'-x'-y'x''),\, y(y'x'y'-x'-y'x''),\, y'x'y'-x'-y'x''),</math></blockquote>which is projectively equivalent to the original curve <math>(x(t),y(t),1)</math>. ==Properties of dual curve==

Dual curve: Difference between revisions