Angle trisection is the division of an arbitrary angle into three equal angles. It was one of the three geometric problems of antiquity for which solutions using only compass and straightedge were sought. The problem was algebraically proved impossible by Wantzel (1836). Although trisection is not possible for a general angle using a Greek construction, there are some specific angles, such as pi/2 and pi radians (90 degrees and 180 degrees, respectively), which can be trisected. Furthermore
Angle - Wikipedia
Can a regular hendecagon be drawn with only a compass, straightedge, and angle quintisector? If so, why exactly? - Quora
Angle trisection - Wikipedia
Mongean Projective Geometry Reverse Engineering
Angle Trisection: A Math Problem Claimed to Not be Solvable and Has Not Been Solved for Over 2200 Years is Solved by Mahesh Bubna in 2022
Trisection of angles-similarly
PPT - Mathematics and Origami PowerPoint Presentation, free download - ID:1540957
Angle Trisection -- from Wolfram MathWorld
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