Solving Cubics With Creases: The Work of Beloch and Lill

  title={Solving Cubics With Creases: The Work of Beloch and Lill},
  author={Thomas C. Hull},
  journal={The American Mathematical Monthly},
  pages={307 - 315}
  • Thomas C. Hull
  • Published 1 April 2011
  • Mathematics
  • The American Mathematical Monthly
Abstract Margharita P. Beloch was the first person, in 1936, to realize that origami (paperfolding) constructions can solve general cubic equations and thus are more powerful than straightedge and compass constructions. We present her proof. In doing this we use a delightful (and mostly forgotten?) geometric method due to Eduard Lill for finding the real roots of polynomial equations. 
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