RTG Problem 38 / Solution

The first move.  

The first move is , no disputes here. But how to answer ?

Mistake.  

The hane at is a mistake. After and , Black is dead with a bulky five or flowery six nakade.

Solution.  

The tesuji is at the 1-2 point.

Variation 1.  

Probably this is the easiest variation. White tries to kill by nakade, but Black lives by seki.

Variation 2.  

If here, blocks and lives unconditionally too.

Variation 3.  

Perhaps the hardest to see is this variation. To answer , occupies the other 1-2 point, and wins the capturing race. In the Chinese book 围棋古谱妙手选, in this diagram is described as an excellent move.