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Vojtěch Jarník IMC
2011 VJIMC
Problem 1
matrix product is nonzero
matrix product is nonzero
Source: VJIMC 2011 2.1
June 1, 2021
linear algebra
matrix
Problem Statement
Let
n
>
k
n>k
n
>
k
and let
A
1
,
…
,
A
k
A_1,\ldots,A_k
A
1
,
…
,
A
k
be real
n
×
n
n\times n
n
×
n
matrices of rank
n
−
1
n-1
n
−
1
. Prove that
A
1
⋯
A
k
≠
0.
A_1\cdots A_k\ne0.
A
1
⋯
A
k
=
0.
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