•Remark: if L1 ºk L2 then the
duplicator has a winning strategy where
it responds with min(L2) to min(L1), and with
max(L2) to max(L1), and vice versa. [why ?]
•
•Lemma If L1· a ºk L2 · b and L1¸ a ºk L2 ¸ b
then (L1 ,a) ºk (L2 ,b)
•
•[how does this help us prove
the theorem ?]