Wikimore

Summary

DescriptionDual.webm	Русский: См. ru:Двойственная кривая English: See en:Dual corve. On the left: the ellipse $(x/2)^{2}+(y/3)^{2}=1$ with tangent lines $xX+yX=1$ for any $X,Y$ , such that $(2X)^{2}+(3Y)^{2}=1$ . On the right: the dual ellipse $(2X)^{2}+(3Y)^{2}=1$ . Each tangent to the first ellipse corresponds to a point on the second one (marked with the same color). To insert add: `[[File:Dual.webm\|thumb\|thumbtime=0.5\|458px]]` (it will show the first frame with additional tangents and corresponding points).
Date	28 October 2016
Source	Own work
Author	Alexei Kopylov

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