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JBMO TST - Macedonia
2012 JBMO TST - Macedonia
2
Macedonian JBMO TST 2012 - Problem 2
Macedonian JBMO TST 2012 - Problem 2
Source: Macedonian JBMO TST 2012
September 17, 2012
geometry proposed
geometry
Problem Statement
Let
A
B
C
D
ABCD
A
BC
D
be a convex quadrilateral inscribed in a circle of radius
1
1
1
. Prove that
0
<
(
A
B
+
B
C
+
C
D
+
A
D
)
ā
(
A
C
+
B
D
)
<
4.
0< (AB+BC+CD+AD)-(AC+BD) < 4.
0
<
(
A
B
+
BC
+
C
D
+
A
D
)
ā
(
A
C
+
B
D
)
<
4.
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