# An Equation for Every Occasion: Fifty-Two Formulas and Why They Matter

###### John M. Henshaw
Publisher:
Johns Hopkins University Press
Publication Date:
2014
Number of Pages:
200
Format:
Hardcover
Price:
29.95
ISBN:
9781421414911
Category:
General
[Reviewed by
Tom French
, on
10/9/2014
]

I thoroughly enjoyed this book by John Henshaw. It is a charming account of 52 mathematical formulas. Each formula has its own short chapter, which typically consists of just three or four pages. The book’s format is intriguing: the formula is presented, and then each variable or constant in the formula is described, followed by a narrative of the history, use, and various applications of the formula.

The tone of the book is signaled already by the cover, where the title is given as

$\frac{\text{an (equation) for}}{\text{every occasion}} = 52 \text{ formulas } + \text{(why) they matter}$

The writing is clear and distinct. Henshaw’s stories about each formula are interesting, humorous, and oftentimes surprising. The range of formulas in this book is appealing, no matter where one’s interests lie. The formulas cover such diverse topics as The Doppler Effect, Estimating Crowd Size, The Mars Curse, Intelligence Quotient, Fracking, Growth and Decay, and Statistics, just to mention a few. This book is a must for teachers who teach formulas. This book provides both interesting stories and historical context to pass on to students.

I found the book to be an easy read. The chapters are written so that one can easily skip around in the book because the stories are not arranged chronologically. As I read the book, I skipped around to whatever ‘tickled my fancy” at the moment.

This book is written for those with a keen interest in mathematics as well as those with a more passive interest in the field. If one is looking for a book with detailed explanations of how each formula solves detailed problems, they will be disappointed. But anyone interested in the history, application, use of formulas, and interesting stories will be delighted.

June 2016: This book is now available also in paperback (ISBN 978-1-4214-1983-1).

Tom French has a B.S. and M.S. degree in Mathematics from Minnesota State University, Mankato. He has 35 years of engineering and business experience with Lockheed Martin, where he served as a multi-functional engineering manager and program manager. He was the program manager for several large product innovations and was one of the leaders who implemented the technology revolution in the banking system in the Russian Federation. Tom has taught mathematics and computers in numerous schools, colleges and universities throughout the United States and the world. In addition, he has taught mathematics at the high school level.