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1971 IMO Longlists
20
20
Part of
1971 IMO Longlists
Problems
(1)
The product is equal two 2 - [IMO LongList 1971]
Source:
1/1/2011
Let
M
M
M
be the circumcenter of a triangle
A
B
C
.
ABC.
A
BC
.
The line through
M
M
M
perpendicular to
C
M
CM
CM
meets the lines
C
A
CA
C
A
and
C
B
CB
CB
at
Q
Q
Q
and
P
,
P,
P
,
respectively. Prove that
C
P
‾
C
M
‾
⋅
C
Q
‾
C
M
‾
⋅
A
B
‾
P
Q
‾
=
2.
\frac{\overline{CP}}{\overline{CM}} \cdot \frac{\overline{CQ}}{\overline{CM}}\cdot \frac{\overline{AB}}{\overline{PQ}}= 2.
CM
CP
⋅
CM
CQ
⋅
PQ
A
B
=
2.
geometry
circumcircle
geometry proposed