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Contests
National and Regional Contests
India Contests
India Pre-Regional Mathematical Olympiad
2012 India PRMO
14
14
Part of
2012 India PRMO
Problems
(1)
2012 preRMO p14, angle chasing, incenter, circumcenter related
Source:
6/17/2019
O
O
O
and
I
I
I
are the circumcentre and incentre of
△
A
B
C
\vartriangle ABC
△
A
BC
respectively. Suppose
O
O
O
lies in the interior of
△
A
B
C
\vartriangle ABC
△
A
BC
and
I
I
I
lies on the circle passing through
B
,
O
B, O
B
,
O
, and
C
C
C
. What is the magnitude of
∠
B
A
C
\angle B AC
∠
B
A
C
in degrees?
geometry
incenter
Angle Chasing