Date: Jan 6, 2012 10:27 AM
Author: Kent Holing
Subject: 2 simple? questions and proposed answers

I often get the following two questions from my non-mathematician friends.

Q1: Why is 1 not a prime? (It divides only 1 and itself.)

Q2: For a, b positive integers (say), why is (-a)(-b) = ab?

I could answer as follows (but with not exactly good success):

Answer to Q1:
If 1 is considered (defined) as a prime, then the fundamenal theorem of arithmetic is not true; and we mathematicians do not like that! Laymen response: !???

Answer to Q2: If not, the distributive law is not true, and we mathematicians do not like that either! Laymen response: !???

Do we have any better answers for our laymen friends?

Kent holing,
NORWAY