(moved from old solution page)
is an improvement. connect at is met by at a.
(The original solution shows at and the variation below, but it fails to at , discussed later.)
kmr - I think here white should play 7 at . It leads to another ko, but better for white.
The original solution shows here first, but it fails to . After , Black wins the capturing race.
kmr - i think black instead of this , should play "a" (if of course is met by white "a" and its succesfull), it leads to another ko. However i think also that if black plays such a move like , then it becomes whole board problem - all depends on nearby stones. In such a condition it must be noted that left white stones are not so big (unless black stones between white groups are killed) - so even outside forcing moves might be bigger for white than saving those stones which originally task was to save.
hnishy: should be throw-in at , then White has only three liberties. Anyway, many things are unclear: stipulation, scope of the problem and how hard Black should try.
Black escapes or gets enough liberties.
hnishy: ugh, White has at a! Maybe we should ignore the left side altogether because this problem is in "connect underneath" section. The book shows four problems on four corners of one full-board diagram without clear borders between problems.
at
kmr - i am not sure about black could play this way. What is his response to white 9 (also there is possibility that white may play instead of , i cant see what black can do, again semai which white wins) ?I tried both "a" and "b" and all ends in some kind of semai which white always win. I guess i miss some unobvious tesuji which should be worth variation, especially when it beats original solution.
hnishy: in this diagram is clearly weak, losing unconditionally.