Prove or disprove the non colinearity of three points
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Prove or disprove: Let $ABCD$ be a quadrilateral in Pasch Geometry for which the following holds $ABcap CD={E}$, $ACcap BD={F}$ and $ADcap BC={G}$. Then the points $E,F,G$ are not collinear.
I tried to prove by contradiction defining a graph on set ${A,B,C,D}$ with edge between two points if they lie on different sides of the line $EFG$ but couldn't arrive to a contradiction. Maybe there is a counterexample in Poincaré Geometry.
geometry
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add a comment |
$begingroup$
Prove or disprove: Let $ABCD$ be a quadrilateral in Pasch Geometry for which the following holds $ABcap CD={E}$, $ACcap BD={F}$ and $ADcap BC={G}$. Then the points $E,F,G$ are not collinear.
I tried to prove by contradiction defining a graph on set ${A,B,C,D}$ with edge between two points if they lie on different sides of the line $EFG$ but couldn't arrive to a contradiction. Maybe there is a counterexample in Poincaré Geometry.
geometry
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2
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The same question on MathOverflow: Prove or disprove the non colinearity of three points. For some advice on corss-posting see this answer on meta and other questions tagged cross-posting.
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– Martin Sleziak
Dec 7 '18 at 6:59
add a comment |
$begingroup$
Prove or disprove: Let $ABCD$ be a quadrilateral in Pasch Geometry for which the following holds $ABcap CD={E}$, $ACcap BD={F}$ and $ADcap BC={G}$. Then the points $E,F,G$ are not collinear.
I tried to prove by contradiction defining a graph on set ${A,B,C,D}$ with edge between two points if they lie on different sides of the line $EFG$ but couldn't arrive to a contradiction. Maybe there is a counterexample in Poincaré Geometry.
geometry
$endgroup$
Prove or disprove: Let $ABCD$ be a quadrilateral in Pasch Geometry for which the following holds $ABcap CD={E}$, $ACcap BD={F}$ and $ADcap BC={G}$. Then the points $E,F,G$ are not collinear.
I tried to prove by contradiction defining a graph on set ${A,B,C,D}$ with edge between two points if they lie on different sides of the line $EFG$ but couldn't arrive to a contradiction. Maybe there is a counterexample in Poincaré Geometry.
geometry
geometry
asked Dec 6 '18 at 21:31
user183294user183294
353
353
2
$begingroup$
The same question on MathOverflow: Prove or disprove the non colinearity of three points. For some advice on corss-posting see this answer on meta and other questions tagged cross-posting.
$endgroup$
– Martin Sleziak
Dec 7 '18 at 6:59
add a comment |
2
$begingroup$
The same question on MathOverflow: Prove or disprove the non colinearity of three points. For some advice on corss-posting see this answer on meta and other questions tagged cross-posting.
$endgroup$
– Martin Sleziak
Dec 7 '18 at 6:59
2
2
$begingroup$
The same question on MathOverflow: Prove or disprove the non colinearity of three points. For some advice on corss-posting see this answer on meta and other questions tagged cross-posting.
$endgroup$
– Martin Sleziak
Dec 7 '18 at 6:59
$begingroup$
The same question on MathOverflow: Prove or disprove the non colinearity of three points. For some advice on corss-posting see this answer on meta and other questions tagged cross-posting.
$endgroup$
– Martin Sleziak
Dec 7 '18 at 6:59
add a comment |
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The same question on MathOverflow: Prove or disprove the non colinearity of three points. For some advice on corss-posting see this answer on meta and other questions tagged cross-posting.
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– Martin Sleziak
Dec 7 '18 at 6:59