RTG Problem 20 / Solution

Solution 1  

The solution is a ko.

Continuation (i)  

at , at , at

If White chooses to capture the snapback stones instead...

Continuation (ii)  

We see that after , Black lives as White will not be able to play at a.

Solution 2  

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 false 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.

Variation  

If , then makes and miai.

Failure

Failure  

Why is a failure? See Snapback Problem 16.