There is one trisection which is of more importance than that of the angle.
In other words, the trisection of any angle, by the use of the straightedge and compasses alone, is impossible.
He also contributes to the history of the trisection of an angle.
A rule for the cubic equation by which the problem of trisection is solved has been given by Cardan.
Geometry versus Algebra; or the trisection of an angle geometrically solved.
His problems of the trisection of the angle, and the duplication of the cube, are curious and interesting.