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1971 IMO Longlists
24
24
Part of
1971 IMO Longlists
Problems
(1)
Prove that the triangle is right angled - [ILL 1971]
Source:
1/1/2011
Let
A
,
B
,
A, B,
A
,
B
,
and
C
C
C
denote the angles of a triangle. If
sin
2
A
+
sin
2
B
+
sin
2
C
=
2
\sin^2 A + \sin^2 B + \sin^2 C = 2
sin
2
A
+
sin
2
B
+
sin
2
C
=
2
, prove that the triangle is right-angled.
trigonometry