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Bogdan Stan
2013 Bogdan Stan
3
Complex eigenvalues; 4 matrices
Complex eigenvalues; 4 matrices
Source:
July 5, 2020
eigenvalue
matries
Matrices
linear algebra
Problem Statement
Let be four
n
×
n
n\times n
n
×
n
real matrices
A
,
B
,
C
,
D
A,B,C,D
A
,
B
,
C
,
D
having the property that
C
+
D
−
1
C+D\sqrt{-1}
C
+
D
−
1
is the inverse of
A
+
B
−
1
.
A+B\sqrt{-1} .
A
+
B
−
1
.
Show that
∣
det
(
A
+
B
−
1
)
∣
2
⋅
∣
det
C
∣
=
det
A
.
\left| \det\left( A+B\sqrt{-1} \right) \right|^2\cdot\left| \det C \right| =\det A.
det
(
A
+
B
−
1
)
2
⋅
∣
det
C
∣
=
det
A
.
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