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SEEMOUS
2011 SEEMOUS
Problem 2
Problem 2
Part of
2011 SEEMOUS
Problems
(1)
a_(ij)*a_(ji)≤0, eigenvalues of A=(a_(ij))
Source: SEEMOUS 2011 P2
6/18/2021
Let
A
=
(
a
i
j
)
A=(a_{ij})
A
=
(
a
ij
)
be a real
n
×
n
n\times n
n
×
n
matrix such that
A
n
≠
0
A^n\ne0
A
n
=
0
and
a
i
j
a
j
i
≤
0
a_{ij}a_{ji}\le0
a
ij
a
ji
≤
0
for all
i
,
j
i,j
i
,
j
. Prove that there exist two nonreal numbers among eigenvalues of
A
A
A
.
matrix
eigenvalues
linear algebra