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5
INAMO 2019 P5
INAMO 2019 P5
Source: INAMO 2019 P5
July 3, 2019
Inamo
algebra
Problem Statement
Given that
a
a
a
and
b
b
b
are real numbers such that for infinitely many positive integers
m
m
m
and
n
n
n
,
⌊
a
n
+
b
⌋
≥
⌊
a
+
b
n
⌋
\lfloor an + b \rfloor \ge \lfloor a + bn \rfloor
⌊
an
+
b
⌋
≥
⌊
a
+
bn
⌋
⌊
a
+
b
m
⌋
≥
⌊
a
m
+
b
⌋
\lfloor a + bm \rfloor \ge \lfloor am + b \rfloor
⌊
a
+
bm
⌋
≥
⌊
am
+
b
⌋
Prove that
a
=
b
a = b
a
=
b
.
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