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Germany Contests
German National Olympiad
2023 German National Olympiad
6
6
Part of
2023 German National Olympiad
Problems
(1)
Ceiling of power of root of cubic equation is divisible by 3
Source: Germany 2023, Problem 6
6/16/2023
The equation
x
3
−
3
x
2
+
1
=
0
x^3-3x^2+1=0
x
3
−
3
x
2
+
1
=
0
has three real solutions
x
1
<
x
2
<
x
3
x_1<x_2<x_3
x
1
<
x
2
<
x
3
. Show that for any positive integer
n
n
n
, the number
⌈
x
3
n
⌉
\left\lceil x_3^n\right\rceil
⌈
x
3
n
⌉
is a multiple of
3
3
3
.
algebra
number theory proposed
algebra proposed
ceiling function
cubic equation