毛起來說三角

by Eli Maor, 毛爾

聽到三角，絕大多數人的腦海可能馬上就閃過一大堆θ、φ、sin、tan、csc、半角公式、倍角公式、和化積、積化和、……，管它實不實用，「卯」起來背就對了，還可以「說」些什麼呢？如果你真的這麼認為，以為三角學只是一個又一個函數與公式，那可大錯特錯了！

　　學校裡，從沒有人告訴你三角的歷史和生命，也沒有人告訴你三角和人類文明如何緊緊相扣；從古埃及的金字塔、砲彈的射程、精確地圖的誕生，到天文測量，全都離不開三角。其實，三角學與現實世界是密不可分的。

　　為了傳達這個觀念，本書作者毛爾教授捨棄教科書式的枯燥寫法，「毛」起來說了許多關於三角的小故事；透過這本書，你將目睹三角學如何從埃及金字塔裡萌芽、從古希臘乃至中世紀天文學家的手中茁壯，你也將認識許許多多偉大的數學家，跟隨他們的腳步，踏進有趣的三角殿堂，一探平面三角學背後的無窮樂趣。

Genres: Mathematics, Nonfiction, History, Science, Textbooks, Teaching

286 pages

First published January 1, 1998

Reviews

[William · Rating 4 out of 5]

A nice refresher of my basic Trig, mixed with some interesting new concepts and historical backgrounds of several important mathematicians. My only complaint is the formatting of the book: many of the diagrams were placed on a page not viewable to where the explanations took place. This made it harder to follow, and resulted in a tendency to skim rather than study. But still, something I'd like to play more with in my spare time.

[Maurizio Codogno · Rating 4 out of 5]

curiosità trigonometriche

Maor lo dice subito: per lui la trigonometria è bellissima, e non si capacita che oramai non venga più insegnata a scuola, con la flebile scusa che con le calcolatrici non serve più avere sistemi per semplificare i conti da fare. Continuo ad avere dubbi sulla bellezza delle trigonometria, ma sono stati scossi un po' da questo testo, che nella prima parte fa una carrellata storica ma nella seconda mostra come tante altre nozioni matematiche che riteniamo ancora oggi utili hanno una correlazione con la trigonometria. Una chicca secondo me è vederla nella proiezione di Mercatore e scoprire che la sua carta geografica non è una proiezione cilindrica come pensano in tanti...
Nota: la versione elettronica del libro è fondamentalmente un PDF, il che significa che o la leggete su un tablet da 10 pollici o su un PC, ma non certo sul furbofono o sul Kindle.

[Tom Concannon · Rating 5 out of 5]

I knew this book was rather “heavy” on the math for a popular level treatise on trigonometry, so I needed to set aside a good chunk of unobstructed time to go through it. After doing so, I was not disappointed! I will use many of the derivations and interesting facts from this book in my future mathematics classes, to not only keep the students on their toes, but to show them how cool trigonometry really is!

[Cristian Sandu · Rating 5 out of 5]

The mix of math and history was interesting and the engaging stories from the past really made me understand the evolution of trigonometry. The author's passion really shines within the pages and it was a pleasant reading for me.

[Nada Khaled · Rating 5 out of 5]

A perfect Trigonometry History

[Ann · Rating 4 out of 5]

Maor does it again in this fascinating collection of essays on trigonometry. The essays are a combination of history, biographical vignettes, proofs and applications ranging from Pythagoras to map projections to Fourier who avoided geometry like the Plague. Maor presents the basic trigonometric functions, cosine and sine in the historical development of their uses from concrete geometry to more abstract number theory, a far cry from the introduction many had in high school. Despite the attention needed to follow the proofs, this is a delightful book and the proofs are well worth the effort. Highly recommended for math tourists and those interested in intellectual history.

[Jef · Rating 5 out of 5]

Lots of back story and neat proofs. Really suplamemts a course in trigonometry.

[Andrew Davis · Rating 2 out of 5]

A bit disappointing. Too much history and not enough trigonometry.

[E.]

a bit over my head, at least for the level of attention I can give right now. looks good though