On the board: black king vs. white king with knight and rook. Could checkmate be done without the white...
Just something I randomly came up with. Sorry if it is a duplicate.
theory checkmate
edited 5 hours ago
Brian Towers
15.5k32967
asked 7 hours ago
Rewan DemontayRewan Demontay
309212
add a comment |
Just something I randomly came up with. Sorry if it is a duplicate.
theory checkmate
edited 5 hours ago
Brian Towers
15.5k32967
asked 7 hours ago
Rewan DemontayRewan Demontay
309212
add a comment |
Just something I randomly came up with. Sorry if it is a duplicate.
theory checkmate
edited 5 hours ago
Brian Towers
15.5k32967
asked 7 hours ago
Rewan DemontayRewan Demontay
309212
Just something I randomly came up with. Sorry if it is a duplicate.
theory checkmate
theory checkmate
edited 5 hours ago
Brian Towers
15.5k32967
asked 7 hours ago
Rewan DemontayRewan Demontay
309212
edited 5 hours ago
Brian Towers
15.5k32967
asked 7 hours ago
Rewan DemontayRewan Demontay
309212
edited 5 hours ago
Brian Towers
15.5k32967
edited 5 hours ago
Brian Towers
15.5k32967
edited 5 hours ago
Brian Towers
15.5k32967
15.5k32967
asked 7 hours ago
Rewan DemontayRewan Demontay
309212
asked 7 hours ago
Rewan DemontayRewan Demontay
309212
asked 7 hours ago
Rewan DemontayRewan Demontay
309212
309212
add a comment |
add a comment |
1 Answer
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I don't think it is possible to forcibly mate the king with rook and knight only.
Proof: The only mating position is with the black king in a corner, the rook giving check from an adjecent square and the knight protecting the rook and covering the escape square.
For simplicity let's say Ka1, Rb1, Nc3. There are 7 other equivalent positions to this one.
If you retro-analyze the position the last move must have been with the rook along the b file from somewhere between b3 and b8. For the folowing analysis it does not matter from where it came.
Then what was black's last move? It certainly was a king move moving from a2, b2 or b1 to the corner (a1). However, since black was not forced to move the king to the corner but could have moved to a3 or c1 (or to b3 if the rook was standing there), the mate cannot be forced.
answered 6 hours ago
user1583209user1583209
12.2k21554
2
For completeness, I guess you have to analyze the possibility that the rook came from b3 preventing Ka3. Of course, then Kxb3 would have been possible.
– D M
6 hours ago
add a comment |
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1 Answer
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1 Answer
1
active
oldest
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active
oldest
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active
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votes
I don't think it is possible to forcibly mate the king with rook and knight only.
Proof: The only mating position is with the black king in a corner, the rook giving check from an adjecent square and the knight protecting the rook and covering the escape square.
For simplicity let's say Ka1, Rb1, Nc3. There are 7 other equivalent positions to this one.
If you retro-analyze the position the last move must have been with the rook along the b file from somewhere between b3 and b8. For the folowing analysis it does not matter from where it came.
Then what was black's last move? It certainly was a king move moving from a2, b2 or b1 to the corner (a1). However, since black was not forced to move the king to the corner but could have moved to a3 or c1 (or to b3 if the rook was standing there), the mate cannot be forced.
answered 6 hours ago
user1583209user1583209
12.2k21554
2
For completeness, I guess you have to analyze the possibility that the rook came from b3 preventing Ka3. Of course, then Kxb3 would have been possible.
– D M
6 hours ago
add a comment |
I don't think it is possible to forcibly mate the king with rook and knight only.
Proof: The only mating position is with the black king in a corner, the rook giving check from an adjecent square and the knight protecting the rook and covering the escape square.
For simplicity let's say Ka1, Rb1, Nc3. There are 7 other equivalent positions to this one.
If you retro-analyze the position the last move must have been with the rook along the b file from somewhere between b3 and b8. For the folowing analysis it does not matter from where it came.
Then what was black's last move? It certainly was a king move moving from a2, b2 or b1 to the corner (a1). However, since black was not forced to move the king to the corner but could have moved to a3 or c1 (or to b3 if the rook was standing there), the mate cannot be forced.
answered 6 hours ago
user1583209user1583209
12.2k21554
2
For completeness, I guess you have to analyze the possibility that the rook came from b3 preventing Ka3. Of course, then Kxb3 would have been possible.
– D M
6 hours ago
add a comment |
I don't think it is possible to forcibly mate the king with rook and knight only.
Proof: The only mating position is with the black king in a corner, the rook giving check from an adjecent square and the knight protecting the rook and covering the escape square.
For simplicity let's say Ka1, Rb1, Nc3. There are 7 other equivalent positions to this one.
If you retro-analyze the position the last move must have been with the rook along the b file from somewhere between b3 and b8. For the folowing analysis it does not matter from where it came.
Then what was black's last move? It certainly was a king move moving from a2, b2 or b1 to the corner (a1). However, since black was not forced to move the king to the corner but could have moved to a3 or c1 (or to b3 if the rook was standing there), the mate cannot be forced.
answered 6 hours ago
user1583209user1583209
12.2k21554
I don't think it is possible to forcibly mate the king with rook and knight only.
Proof: The only mating position is with the black king in a corner, the rook giving check from an adjecent square and the knight protecting the rook and covering the escape square.
For simplicity let's say Ka1, Rb1, Nc3. There are 7 other equivalent positions to this one.
If you retro-analyze the position the last move must have been with the rook along the b file from somewhere between b3 and b8. For the folowing analysis it does not matter from where it came.
Then what was black's last move? It certainly was a king move moving from a2, b2 or b1 to the corner (a1). However, since black was not forced to move the king to the corner but could have moved to a3 or c1 (or to b3 if the rook was standing there), the mate cannot be forced.
answered 6 hours ago
user1583209user1583209
12.2k21554
edited 5 hours ago
answered 6 hours ago
user1583209user1583209
12.2k21554
answered 6 hours ago
user1583209user1583209
12.2k21554
answered 6 hours ago
user1583209user1583209
12.2k21554
12.2k21554
2
For completeness, I guess you have to analyze the possibility that the rook came from b3 preventing Ka3. Of course, then Kxb3 would have been possible.
– D M
6 hours ago
add a comment |
2
For completeness, I guess you have to analyze the possibility that the rook came from b3 preventing Ka3. Of course, then Kxb3 would have been possible.
– D M
6 hours ago
2
2
For completeness, I guess you have to analyze the possibility that the rook came from b3 preventing Ka3. Of course, then Kxb3 would have been possible.
– D M
6 hours ago
For completeness, I guess you have to analyze the possibility that the rook came from b3 preventing Ka3. Of course, then Kxb3 would have been possible.
– D M
6 hours ago
add a comment |
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