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IMC
1995 IMC
5
5
Part of
1995 IMC
Problems
(1)
IMC 1995 Problem 5
Source: IMC 1995
2/18/2021
Let
A
A
A
and
B
B
B
be real
n
×
n
n\times n
n
×
n
matrices. Assume there exist
n
+
1
n+1
n
+
1
different real numbers
t
1
,
t
2
,
…
,
t
n
+
1
t_{1},t_{2},\dots,t_{n+1}
t
1
,
t
2
,
…
,
t
n
+
1
such that the matrices
C
i
=
A
+
t
i
B
,
i
=
1
,
2
,
…
,
n
+
1
C_{i}=A+t_{i}B, \,\, i=1,2,\dots,n+1
C
i
=
A
+
t
i
B
,
i
=
1
,
2
,
…
,
n
+
1
are nilpotent. Show that both
A
A
A
and
B
B
B
are nilpotent.
linear algebra
Nilpotent