In: Advanced Math
Let α, β be cuts as defined by the following:
1) α ≠ ∅ and α ≠ Q
2) if r ∈ α and s ∈ Q satisfies s < r, then s ∈ α.
3) if r ∈ α, then there exists s ∈ Q with s > r and s ∈ α.
Let α + β = {r + s | r ∈ α and s ∈ β}.
Show that the set of all cuts R with the addition defined above satisfies the axioms for addition (closed, associative, symmetric, identity, inverse)