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Golden Opportunities - mistake?
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Author:  emeraldemon [ Fri Nov 12, 2010 8:27 am ]
Post subject:  Golden Opportunities - mistake?

So here's the problem on pg 59, black to play:

Click Here To Show Diagram Code
[go]$$B Position 17
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . X . , X X X . . , . . . . . , . . . |
$$ | . . X X O O O X X X . . . . . . . . . |
$$ | . X O O . . . O O X . . . . . . . . . |
$$ | . . . . . . . . O . . . . . . . . . . |
$$ ---------------------------------------[/go]


After a few failure diagrams, it shows this success:

Click Here To Show Diagram Code
[go]$$B Diagram 5
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . X . , X X X . . , . . . . . , . . . |
$$ | . . X X O O O X X X . . . . . . . . . |
$$ | . X O O . 4 6 O O X . . . . . . . . . |
$$ | . 7 5 . 2 1 3 . O . . . . . . . . . . |
$$ ---------------------------------------[/go]



But then it has this diagram:
Click Here To Show Diagram Code
[go]$$B Diagram 6
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . X . , X X X . . , . . . . . , . . . |
$$ | . . X X O O O X X X . . . . . . . . . |
$$ | . X O O . 2 . O O X . . . . . . . . . |
$$ | . 5 3 a 4 b 1 . O . . . . . . . . . . |
$$ ---------------------------------------[/go]

"From the result of Diagram 1 it can be appreciated that black 1 is a vital point. After the sequence white 2 to black 5, A and B are equivalent options and white is dead."

It doesn't seem like this move works to me:

Click Here To Show Diagram Code
[go]$$B Failure?
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . X . , X X X . . , . . . . . , . . . |
$$ | . . X X O O O X X X . . . . . . . . . |
$$ | . X O O . 3 . O O X . . . . . . . . . |
$$ | . . . . 4 2 1 . O . . . . . . . . . . |
$$ ---------------------------------------[/go]


The other move (diagram 5) seems like the right answer. Is this a mistake in the book or am I missing something? Does starting at either point work?

Author:  Stable [ Fri Nov 12, 2010 8:34 am ]
Post subject:  Re: Golden Opportunities - mistake?

Click Here To Show Diagram Code
[go]$$B Killed
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . X . , X X X . . , . . . . . , . . . |
$$ | . . X X O O O X X X . . . . . . . . . |
$$ | . X O O 6 3 5 O O X . . . . . . . . . |
$$ | . . 7 . 4 2 1 . O . . . . . . . . . . |
$$ ---------------------------------------[/go]


Black just connects, as above, the rest is inevitable.

Author:  emeraldemon [ Fri Nov 12, 2010 8:37 am ]
Post subject:  Re: Golden Opportunities - mistake?

You're right, I should have noticed that. So I guess both moves work?

Author:  Stable [ Fri Nov 12, 2010 8:42 am ]
Post subject:  Re: Golden Opportunities - mistake?

Click Here To Show Diagram Code
[go]$$B Killed
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . X . , X X X . . , . . . . . , . . . |
$$ | . . X X O O O X X X . . . . . . . . . |
$$ | . X O O 4 3 6 O O X . . . . . . . . . |
$$ | . . 8 . 5 7 1 . O . . . . . . . . . . |
$$ ---------------------------------------[/go]


I'm not sure, what about this seki? (2 at 7) Suggests the best b can do here is 7 at 8 and then fight the ko.

Author:  Li Kao [ Fri Nov 12, 2010 8:55 am ]
Post subject:  Re: Golden Opportunities - mistake?

Stable wrote:
Click Here To Show Diagram Code
[go]$$B Killed
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . X . , X X X . . , . . . . . , . . . |
$$ | . . X X O O O X X X . . . . . . . . . |
$$ | . X O O 4 3 6 O O X . . . . . . . . . |
$$ | . . 8 . 5 7 1 . O . . . . . . . . . . |
$$ ---------------------------------------[/go]


I'm not sure, what about this seki? (2 at 7) Suggests the best b can do here is 7 at 8 and then fight the ko.

Your 5 looks wrong to me.
Oh I missed there was a 2 at your 7.
Click Here To Show Diagram Code
[go]$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . X . , X X X . . , . . . . . , . . . |
$$ | . . X X O O O X X X . . . . . . . . . |
$$ | . X O O 4 3 5 O O X . . . . . . . . . |
$$ | . . 6 . 7 . 1 . O . . . . . . . . . . |
$$ ---------------------------------------[/go]

Author:  Bill Spight [ Fri Nov 12, 2010 8:59 am ]
Post subject:  Re: Golden Opportunities - mistake?

Never mind.

I misinterpreted some English. :mrgreen:

Author:  Bill Spight [ Fri Nov 12, 2010 9:01 am ]
Post subject:  Re: Golden Opportunities - mistake?

Click Here To Show Diagram Code
[go]$$B Death in the hane
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . X . , X X X . . , . . . . . , . . . |
$$ | . . X X O O O X X X . . . . . . . . . |
$$ | . X O O 7 4 3 O O X . . . . . . . . . |
$$ | . . 5 6 . 2 1 . O . . . . . . . . . . |
$$ ---------------------------------------[/go]



Click Here To Show Diagram Code
[go]$$B Variation
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . . . . . . . . . . . . . . . . . . . |
$$ | . X . , X X X . . , . . . . . , . . . |
$$ | . . X X O O O X X X . . . . . . . . . |
$$ | . X O O . 4 3 O O X . . . . . . . . . |
$$ | . 7 5 . 6 2 1 . O . . . . . . . . . . |
$$ ---------------------------------------[/go]

Author:  Stable [ Mon Nov 15, 2010 5:07 am ]
Post subject:  Re: Golden Opportunities - mistake?

Thanks Bill!

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