Kempe's universality theorem

In algebraic geometry, Kempe's universality theorem states that any bounded subset of an algebraic curve may be traced out by the motion of one of the joints in a suitably chosen linkage. It is named for British mathematician Alfred B. Kempe, who in 1876 published his article On a General Method of describing Plane Curves of the nth degree by Linkwork, which showed that for any arbitrary algebraic plane curve, a linkage can be constructed that draws the curve.

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