TY - GEN AU - Ben-Ari, Mordechai TI - Mathematical surprises SN - 9783031135651 AV - QA99 PY - 2022///] CY - Switzerland: PB - Springer Cham N1 - Chapter 1: The Collapsing Compass Chapter 2: Trisection of an Angle Chapter 3: Squaring the Circle Chapter 4: The Five-Color Theorem Chapter 5: How to Guard a Museum Chapter 6: Induction Chapter 7: Solving Quadratic Equations Chapter 8: Ramsey Theory Chapter 9: Langford’s Problem Chapter 10: The Axioms of Origami Chapter 11: Lill’s Method and the Beloch Fold Chapter 12: Geometric Constructions Using Origami Chapter 13: A Compass Is Sufficient Chapter 14: A Straightedge and One Circle is Sufficient Chapter 15: Are Triangles with Equal Areas and Perimeters Congruent? Chapter 16: Construction of a Regular Heptadecagon N2 - This is open access book provides plenty of pleasant mathematical surprises. There are many fascinating results that do not appear in textbooks although they are accessible with a good knowledge of secondary-school mathematics. This book presents a selection of these topics including the mathematical formalization of origami, construction with straightedge and compass (and other instruments), the five- and six-color theorems, a taste of Ramsey theory and little-known theorems proved by induction. Among the most surprising theorems are the Mohr-Mascheroni theorem that a compass alone can perform all the classical constructions with straightedge and compass, and Steiner's theorem that a straightedge alone is sufficient provided that a single circle is given. The highlight of the book is a detailed presentation of Gauss's purely algebraic proof that a regular heptadecagon (a regular polygon with seventeen sides) can be constructed with straightedge and compass. Although the mathematics used in the book is elementary (Euclidean and analytic geometry, algebra, trigonometry), students in secondary schools and colleges, teachers, and other interested readers will relish the opportunity to confront the challenge of understanding these surprising theorems. Supplementary material to the book can be found at https://github.com/motib/suprises. ---Summary provided by the publisher UR - https://doi.org/10.1007/978-3-031-13566-8 ER -