EVENT
BOARDSIZE 19
SETUP W D17 P17 Q5 R6 Q7 
SETUP B R16 C4 Q3 O3 R4 R5 
MARK 6@O3 5@Q7 4@R4 3@R6 2@R5 1@Q5 A@Q15
COM
Problem 48. White to play.  

This time White has made a high approach with 1. Instead of the
diagonal move at A, Black plays the joseki to 6. How should White
continue ? 
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W 1 R13
USER
CORRECT ANSWER
ENDUSER
COM
Correct Answer.

White should pincer the black stone in the upper right corner
with 1.
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  VAR
  W 1 R11
  COM
  Failure.

  Playing the joseki move of White 1 is not good.
  ENDCOM
  B 2 R13
  MARK A@R8
  COM
  Black can settle his stones in the upper right corner by extending
  to 2 and threaten to invade White's position at the bottom with
  a move at A. (See Problems 30, 33, 36, 39, and 42 in Get Strong
  at Invading.)
  <=
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  ENDVAR
B 2 Q15
COM
If Black plays 2, ...
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W 3 P13
COM
... White will jump to 3 and make a moyo on the right side. Black's
stones are still under attack, so White will end in sente.
<=
ENDCOM