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Austrian-Polish
1995 Austrian-Polish Competition
9
9
Part of
1995 Austrian-Polish Competition
Problems
(1)
(n - 1)(m- 1)(x^{n+m} + y^{n+m}) + (n + m - 1)(x^ny^m + x^my^n) >= ...
Source: Austrian Polish 1995 APMC
4/26/2020
Prove that for all positive integers
n
,
m
n,m
n
,
m
and all real numbers
x
,
y
>
0
x, y > 0
x
,
y
>
0
the following inequality holds:
(
n
−
1
)
(
m
−
1
)
(
x
n
+
m
+
y
n
+
m
)
+
(
n
+
m
−
1
)
(
x
n
y
m
+
x
m
y
n
)
≥
n
m
(
x
n
+
m
−
1
y
+
x
y
n
+
m
−
1
)
.
(n - 1)(m- 1)(x^{n+m} + y^{n+m}) + (n + m - 1)(x^ny^m + x^my^n)\\ \\ \ge nm(x^{n+m-1}y + xy^{n+m-1}).
(
n
−
1
)
(
m
−
1
)
(
x
n
+
m
+
y
n
+
m
)
+
(
n
+
m
−
1
)
(
x
n
y
m
+
x
m
y
n
)
≥
nm
(
x
n
+
m
−
1
y
+
x
y
n
+
m
−
1
)
.
inequalities
algebra