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Old Kyiv MO Geometry
Kyiv City MO 1984-93 - geometry
1993.10.4
1993.10.4
Part of
Kyiv City MO 1984-93 - geometry
Problems
(1)
a cos А + bcos В + с cos С <= р 1992 Kyiv City MO 10.4
Source:
7/20/2021
Prove theat for an arbitrary triangle holds the inequality
a
cos
A
+
b
cos
B
+
c
cos
C
≤
p
,
a \cos A+ b \cos B + c \cos C \le p ,
a
cos
A
+
b
cos
B
+
c
cos
C
≤
p
,
where
a
,
b
,
c
a, b, c
a
,
b
,
c
are the sides of the triangle,
A
,
B
,
C
A, B, C
A
,
B
,
C
are the angles,
p
p
p
is the semiperimeter.
inequalities
trigonometry
geometric inequality
geometry