What is the largest number less than 1? If x and y are any of two different positive numbers, which is larger, x2 + y2 or 2xy? What do you get if you cross a cube and an octahedron? Discover the surprising answers as David Wells conclusively proves that: you Are a mathematician Praise for David Wells's The Penguin Dictionary of Curious and Interesting Numbers. "This is a fascinating, strange, and probably unique book, one that I will look at again and again. As soon as I had taken a good look at it, I went out and bought three more copies to give to friends." —New Scientist. "David Wells's book about curious and interesting numbers is a quirky classic." —William Dunham Author, Journey Through Genius. Are you on friendly terms with numbers? You will be after reading this delightful introduction to the fascinating and challenging world of mathematics. Bestselling author David Wells, a Cambridge math scholar and former teacher, explores the many patterns, properties —and problems —associated with numbers in a witty, thoroughly engaging style that is both entertaining and informative. Whether you are a math aficionado or whether you, as the author puts it, "panic and start sweating at the sight of a sum," Wells makes one point abundantly clear: You Are a Mathematician. From basic arithmetic to algebraic equations, from the purely practical to the abstract, this is an ideal guide to the potential and pleasures of math. Surprising patterns emerge from the simplest groupings of numbers. The many secrets hidden inside of triangles are revealed, as are the origins of a host of mathematical theories and principles, from Aristotle to Euclid and Galileo. On a journey from the ancient Greeks to quantum theory, Wells shares intriguing anecdotes from history, such as how eighteenth-century European military commanders calculated how many cannonballs their enemies had stacked up next to their cannons. David Wells invites us to discover the sense of wonder and fun that is so much a part of mathematics. Mathematical thinking is often very much like a game, relying on cunning tactics, deep strategy, and brilliant combinations as much as on observation, analogy, and informed guesswork. To illustrate, Wells includes over 100 brainteasing puzzles and problems, ranging from Ptolemy's theorem to Euler's famous solution to the Königsberg bridge problem and Koch's snowflake curve. Modern-day computer buffs will also enjoy the underground classic, the Game of Life, invented by Princeton mathematician John Conway. Offering a comprehensive and stimulating look at the myriad aspects of mathematics —whether as a household helper or an invaluable tool of science —You Are a Mathematician covers a wide range of topics and applications. It is an ideal guide to the potential and pleasures to be found in math.