# BQM80

This is a problem in a book I'm reading:

Black to play and capture the two white stones.
The book tells me Black's best move is *a*, and White's
best response is *c*, and I understand the rest of
the sequence. But why is White's best move *c*?
What happens if White plays *b* instead?

(note: Thanks to everyone. Misread the book. Black plays at *b*
not *a* ...)

unkx80: Was there a typo in the book? I think the solution should be this.

icepick: This is what is termed the Crosscut Tesuji, from TesujiTheBook. unkx80's solution is correct.

This is a given variation that can be tricky for Black. As Dieter pointed out, is the correct follow up.

This is Dieter's proposed move (). It looks good - this way Black not only captures the two cutting stones, but also the marked stone and . - Andre Engels, after improvement/correction by Dieter

unkx80: While you are at it consider this one. Of course you would have known the correct solution already, but what if...?

Andre Engels: Dieter's descent again resolves the problem.
Charles It may do; but now White at *a* is a reading problem. Andre Engels: The solution seems to be that Black connects at *b* and wins the capturing race by one move. But this position is surely more complicated than the books usually show.

Bill: Shouldn't Black descend again with ? Then it's me ari me nashi. The above is one variation. If is at , is at .