RTG Problem 44 / Solution

Solution  

Black can get a ko by playing at a; White can kill by capturing at b.

Failure

Failure  

Can Black live unconditionally by connecting at ? The answer is no, Black is unconditionally dead after .

Failure  

If here, then and kills. Note that this is not a seki: due to the weakness induced by the stone, Black's eyespace is almost filled with three stones.

Failure  

tries to lure White into a connect and die and capture three to make an eye, but can play from the inside. Subsequently, a and b are miai. Note that if at a, then Black at lives!