Beginner Exercise 2 / Solution

Sub-page of BeginnerExercise2
[Diagram]

Solution

After B3, White can't play at a because of shortage of liberties.

If White plays at b then Black answers at a. White can capture Black's stones, but that leaves her with a three in a row shape.

See also rectangular six in the corner.


Failure diagrams (Jasonred, ArnoHollosi):

[Diagram]

Incorrect: leads to ko for life

(The question says "kill White without ko".)

[Diagram]

Variation

What if White plays somewhere else?

If White answers with W2 here, Black plays B3. White would like to play at B3 as well, if Black plays at a or b. Why?

[Diagram]

Bulky five

Because if we add WC to the 2x3 square we get a shape called bulky five (marked). And that shape can be killed by playing on the vital point, marked with a square.

[Diagram]

Bulky five (again)

So, after B1 and W2 in the variation diagram, we have a bulky five shape, with one point already occupied by Black. However, the vital point marked with a square has not been played yet. That is why Black plays at B3 next. (And that is why White trying to live with W2 in the first diagram seems like a good idea - but fails as well.)

Try to memorize the bulky five shape. It occurs over and over again.


See also:



This is a copy of the living page "Beginner Exercise 2 / Solution" at Sensei's Library.
(OC) 2007 the Authors, published under the OpenContent License V1.0.
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