Expert: Paul Klarreich - 6/17/2009

Question
which number system is this true for.....this is no doubt a graduate level or
higher question.

Q: which number system is this true for (a+b)^2 = a^2 + b^2

Answer
Questioner:   Daniel
Country:  United States
Category:  Advanced Math
Private:  No
 
Subject:  Number Systems
Question:  which number system is this true for.....this is no doubt a graduate level or
higher question.

Q: which number system is this true for (a+b)^2 = a^2 + b^2
...............................................
Hi, Daniel,

I suppose, (besides being your usual beginning-algebra error) that you could try the system of MOD-2 arithmetic.  In this, anything even becomes 0 and anything odd becomes 1, so:

(a + b)^2 = a^2 + 2ab + b^2 = a^2 + 0ab + b^2 = a^2 + b^2.

Does this help?