All you need to know about Carpenter's Square - 22

Diagram 22.1: White to play

We already learned that attacking at 'a' from outside is not working. What else?

Diagram 22.2: Solution

White 1 is urgent. If Black 2 connects, after forcing moves White 3 and *w5*, White 7 simply reduces the eyespace to kill.

Diagram 22.3: Variation

If *b2*, White 3 is a good move. White again can kill straight-forwardly. Black 4 at 'a' is useless too.

Diagram 22.4: Variation

White 3 is an alternative way to kill. After *w9*, 'a' and 'b' are miai points.

Diagram 22.5: White fails

White 1 gives away the key point to black. There is no way to kill this corner any more.

Conclusion: This shape is quite simple. As long as white gets the key 2-2 point, black has no chance.