Prove that the bargaining set is covariant under strategic equivalence. In other words, if (N; v) and (N; w) are two coalitional games with the same set of players, and if there exist a > 0 and b ∈ RN such that
ω(S) = av(S) + b(S), ∀S ⊆ N.
then for every coalitional structure B,
x ∈ M(N; v;B) ⇐⇒ ax + b ∈ M(N; w;B).