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36
2000 Guts #36: Magnitude of angle
2000 Guts #36: Magnitude of angle
Source:
October 25, 2014
geometry
LaTeX
inradius
trigonometry
trig identities
Law of Cosines
Problem Statement
If, in a triangle of sides
a
,
b
,
c
a, b, c
a
,
b
,
c
, the incircle has radius
b
+
c
−
a
2
\frac{b+c-a}{2}
2
b
+
c
−
a
, what is the magnitude of
∠
A
\angle A
∠
A
?
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