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2
right-angled triangle
right-angled triangle
Source:
June 2, 2010
trigonometry
Problem Statement
Prove that the triangle ABC is right-angled if it holds:
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
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