Editing Angle trisection (section)

===With an auxiliary curve===
<gallery heights="320" widths="320">
File:Archimedean spiral trisection.svg|Trisection using the Archimedean spiral
File:01-Angel Trisection.svg|Trisection using the Maclaurin trisectrix
</gallery>There are certain curves called [[trisectrix|trisectrices]] which, if drawn on the plane using other methods, can be used to trisect arbitrary angles.<ref>Jim Loy {{cite web|url=http://www.jimloy.com/geometry/trisect.htm |title=Trisection of an Angle |access-date=2013-11-04 |url-status=dead |archive-url=https://web.archive.org/web/20131104113041/http://www.jimloy.com/geometry/trisect.htm |archive-date=November 4, 2013 }}</ref>  Examples include the [[Trisectrix of Maclaurin|trisectrix of Colin Maclaurin]], given in [[Cartesian coordinate system|Cartesian coordinates]] by the [[Implicit curve|implicit equation]]
:<math>2x(x^2+y^2)=a(3x^2-y^2),</math>
and the [[Archimedean spiral]].  The spiral can, in fact, be used to divide an angle into ''any'' number of equal parts.
Archimedes described how to trisect an angle using the Archimedean spiral in [[On Spirals#Trisecting an angle|On Spirals]] around 225 BC.