The solution is a ko.
at
,
at
,
at
If White chooses to capture the snapback stones instead...
We see that after , Black lives as White will not be able to play at a.
White also has this response.
If White loses the ko, this is better because Black will not have played at a.
If White wins the ko, White will connect at , creating a temporary seki, whith the outside Black stones dead. The result is the Solution 1 diagram.
So in terms of points, this is better for White than the Solution 1 diagram above. However, the other way gives White a local ko threat by capturing the two Black stones as in the Continuation (i) diagram. If that threat is crucial, then the other way is better.
If , then
makes
and
miai.
Why is a failure? See Snapback Problem 16.
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