Sample problem in chapter 1 (Revised GRE)

[euphony_bakersfield]

I have a question concerning the sample question on page 25 in volume 1. The question considers the equation below.

ab = | a | x | b |

The book states that ab > 0 must be true. However, unless I have a misunderstanding, it appears that if either a or b (or both) are zero, the equation is true. For example, if a = -1 and b = 0, we have...

ab = (-1)(0) = 0
| a | x | b | = 1 x 0 = 0

In this case, the equation is true, but ab = 0 (implying ab > 0 need not be true). Please let me know if I have an error in my understanding, and thanks for your time.

[jen]

Hi Euphony,

You are correct. The problem should say "ab does not equal zero" in the text, but doesn't. Thanks for reporting that!

Jennifer