RTG Problem 35 / Solution

Solution  

The best Black can get is to connect back the two Black stones in sente, leaving the endgame benefit of capturing two White stones at a.

Note that in this diagram, both and are tesuji.

Caution  

Note that cannot hope to save the two White stones. is a good move, and White is killed.

Tesuji  

cannot Block, because can cut. After that, makes a snapback. Now White cannot live. ( at a, , Wb still lives, of course)

Not tesuji  

and are tesujis, because cannot cut directly. captures all the Black stones.

Dangerous  

is dangerous. and eke out a ko, and the life and death of the entire White group now depends on this huge ko.

Dangerous  

Similarly, here is also very dangerous. After , White can only live by a ko.

Failure  

forces , and looks like is a tesuji that kills?

Failure  

If , then crawls and connects out.

Failure  

But can simply descend. With , Black happily sees the stones coming home. And then squeezes. White has in fact prevented the guest (three Black stones) from leaving!