I have two sets A,B where B is not the empty set. b is an element of B and a is an element of A.

The function defined by j(a)=(a,b) where (a,b) is an element of AxB.

Show j: A---> AxB for all b in B is one to one.

So I want to show that if j(a1)=j(a2) that implies that a1=a2. I just don't know how to go about proving this. I tried to just assume that j(a1)=j(a2) but I don't think I can just assume that.

Thanks so much for any help!!