Author: Lindsey Fallow & Dawn Griffiths
Publisher: O'Reilly, 2010
Aimed at: Those with an aversion to maths
Pros: Uses an approach that works
Cons: Doesn't go very far
Reviewed by: Mike James
2D geometry is basic to so many things, including any attempt at programming graphics. This book aims to introduce the basic ideas without frightening the non-mathematical reader.
It sort of works - but there are some reservations.
Following the usual form of a "Head First" title there are lots of photos, asides, quizzes, activities and so on - and it does help.
The ideas are all introduced as part of a "real world" problem - a fictitious homicide is used to introduce angles and properties of angles as you try to work out the CSI-take on geometry.
Later stories are similarly angled (pun intended) to capture the imagination of teenagers - skate boarding, designing a pattern for a screen graphic and so on. Again all of this mostly works even if you initially might feel a bit embarrassed by the cartoon-like characters - hey dude where's my angle. But if you stay with it you do get immersed in the problems and the geometry needed to solve them.
There are severn chapters:
Chapter 1. Finding Missing Angles
Chapter 2. Similarity and Congruence
Chapter 3. The Pythagorean Theorem
Chapter 4. Triangle Properties
Chapter 5. Circles
Chapter 6. Quadrilaterals
Chapter 7. Regular Polygons
The book really does start from the basic idea of what an angle is and doesn't get very far. You do learn Pythagoras via the usual geometric demonstration rather than by proof and both proof and algebra are down played at every turn.
It is about getting the student to really understand and imagine the geometric properties under discussion. This is geometry by feel and experience, rather than proof, and there is nothing wrong with the approach.
This is not a book that is going to be of any use to the student who has even the slightest grasp of, or aptitude for, math and geometry in particular. It is such a low level and such a low information density that it really is only for the maths non-starter or refuser.
So as long as you realise that this is very basic 2D geometry and it isn't going to be of direct help if you are struggling with a traditional course on geometric proofs then it's a good book.