SnotNose: A comment on this solution: - make an L+1 group with a weak leg. It has the same status as an L+1 group with a strong leg (one in which is a Black stone): Black can live, White can kill. Since White must play , Black lives with . I believe this is the correct solution.
unkx80: This is a dead L group. If at , then White still plays , and the result is the same.