MathDB
Problems
Contests
National and Regional Contests
Korea Contests
South Korea USCM
2019 Korea USCM
4
unitary matrices, determinant
unitary matrices, determinant
Source: 2019 South Korea USMC P4
August 13, 2020
linear algebra
determinant
unitary matrix
college contests
Problem Statement
For any
n
×
n
n\times n
n
×
n
unitary matrices
A
,
B
A,B
A
,
B
, prove that
∣
det
(
A
+
2
B
)
∣
≤
3
n
|\det (A+2B)|\leq 3^n
∣
det
(
A
+
2
B
)
∣
≤
3
n
.
Back to Problems
View on AoPS