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2010 CHMMC Winter
1
2010 Winter Team #1
2010 Winter Team #1
Source:
March 19, 2022
matrix
algebra
Problem Statement
A matrix
M
M
M
is called idempotent if
M
2
=
M
M^2 = M
M
2
=
M
. Find an idempotent
2
×
2
2 \times 2
2
×
2
matrix with distinct rational entries or write “none” if none exist.
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