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On points constructible from conics. (English) Zbl 0878.51005
It is known that some geometric constructions are impossible if one uses just a straightedge and compass. What if one is allowed to use conics? It was known to the ancient Greeks that (i) duplication of the cube is possible by using a parabola (Menaechmus), (ii) trisection of an arbitrary angle is possible by using a hyperbola (Pappus), (iii) a regular heptagon can be constructed (Archimedes). In the present paper, the author considers the problem of which points are constructible from conics. In particular, he determines which regular polygons are conic-constructible.

##### MSC:
 51M15 Geometric constructions
##### Keywords:
points; regular polygons; conic-constructible
Full Text:
##### References:
 [1] L. Bieberbach,Theorie der Geometrischen Konstruktionen, Birkhäuser, Bern, 1952. [2] D.J.H. Garling,A Course in Galois Theory, Cambridge University Press, Cambridge, 1986. · Zbl 0608.12025 [3] T.L. Heath,A History of Greek Mathematics, Oxford University Press, Oxford, 1960. [4] T.L. Heath,A Manual of Greek Mathematics, Dover Publications, New York, 1963. · Zbl 0113.00105 [5] N. Jacobson,Basic Algebra I, W.H. Freeman & Co., New York, 1985. [6] D. Robinson,A Course in the Theory of Groups, Springer-Verlag, New York, 1982. · Zbl 0483.20001