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Hanoi Open Mathematics Competition
2010 Hanoi Open Mathematics Competitions
4
4
Part of
2010 Hanoi Open Mathematics Competitions
Problems
(1)
a \in (1,9) such (a - 1/a) is an integer (HOMC 2010 J Q4)
Source:
7/25/2019
How many real numbers
a
∈
(
1
,
9
)
a \in (1,9)
a
∈
(
1
,
9
)
such that the corresponding number
a
−
1
a
a- \frac1a
a
−
a
1
is an integer?(A):
0
0
0
, (B):
1
1
1
, (C):
8
8
8
, (D):
9
9
9
, (E) None of the above.
number theory
Integer