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Problem
Problem
If the incircle of the triangle
A
B
C
ABC
A
B
C
passes through its circumcentre, then the
cos
A
+
cos
B
+
cos
C
\boldsymbol{\cos A + \cos B + \cos C}
c
o
s
A
+
c
o
s
B
+
c
o
s
C
is a.
−
2
-2
−
2
b.
2
\sqrt{2}
2
c.
−
2
-\sqrt{2}
−
2
d. None of these
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