Originally Posted by

**scottie.mcdonald** just want to make sure that my thinking is on the right track here. we are working with abstract algebra, more specifically we are working with groups. so the + symbol should have a circle around it:

Given (a,b)E of Z x Z* [a,b are elements of integers times integers with no zeros]

show that [(-a,b)] is an additive inverse of [(a,b), that is [(a,b)] + [(-a,b)]=[(0,1)]

What I think I have to do:

show that [(a,b)]+[(-a,b)] = [(-a,b)]+[(a,b)] (or in relation to)

which will give the identity element [(0,1)]

so using the communitive law:

[ab + b-a,bb] = [(0.1)]

again note that the + symbol shoul have a circle around it. Any advice would be good. If you need clarification on anything, let me know. Thank you.