 Leonhard Euler was one of the most prolific mathematicians that have ever lived. This book examines the huge scope of mathematical areas explored and developed by Euler, which includes number theory, combinatorics, geometry, complex variables and many more. The information known to Euler over 300 years ago is discussed, and many of his advances are reconstructed. Readers will be left in no doubt about the brilliance and pervasive influence of ... |  First developed during WW2, the Trachtenberg speed system makes possible high-speed arithmetical calcula tions with a remarkable degree of accuracy. The system has e ven been known to beat computer calculations - in some insta nces - in terms of speed ' ... |