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Problems
Contests
National and Regional Contests
Serbia Contests
Serbia JBMO TST
2011 Serbia JBMO TST
3
3
Part of
2011 Serbia JBMO TST
Problems
(1)
Geometry problem
Source:
2/10/2019
Let
△
A
B
C
\triangle ABC
△
A
BC
be a right-angled triangle and
B
C
>
A
C
BC > AC
BC
>
A
C
.
M
M
M
is a point on
B
C
BC
BC
such that
B
M
=
A
C
BM = AC
BM
=
A
C
and
N
N
N
is a point on
A
C
AC
A
C
such that
A
N
=
C
M
AN = CM
A
N
=
CM
. Find the angle between
B
N
BN
BN
and
A
M
AM
A
M
.
geometry
trigonometry