Jordan canonical form of strictly upper or lower triangular matrices of even order n and rank n-1.
Clash Royale CLAN TAG#URR8PPP
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I am trying to find the jordan canonical form of $
A=
left[ beginarraycccc
0 & 0 & 0 & 0 \
3 & 0 & 0 & 0 \
0 & 2 & 0 & 0 \
0 & 0 & 1 & 0 \
endarray right]
$.
In this process I found $0$ is the only eigen value with algebraic multiplicity $4$ and geometric multiplicity $1$ so jordan canonical form should have only one 0-jordan block of order $4$.
But as $A^3 = 0$, we have $x^3$ as minimal polynomial and that suggest the largest $0$-jordan block can be of order $3$.
Please help, where am I wrong?
linear-algebra linear-transformations
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up vote
1
down vote
favorite
I am trying to find the jordan canonical form of $
A=
left[ beginarraycccc
0 & 0 & 0 & 0 \
3 & 0 & 0 & 0 \
0 & 2 & 0 & 0 \
0 & 0 & 1 & 0 \
endarray right]
$.
In this process I found $0$ is the only eigen value with algebraic multiplicity $4$ and geometric multiplicity $1$ so jordan canonical form should have only one 0-jordan block of order $4$.
But as $A^3 = 0$, we have $x^3$ as minimal polynomial and that suggest the largest $0$-jordan block can be of order $3$.
Please help, where am I wrong?
linear-algebra linear-transformations
add a comment |Â
up vote
1
down vote
favorite
up vote
1
down vote
favorite
I am trying to find the jordan canonical form of $
A=
left[ beginarraycccc
0 & 0 & 0 & 0 \
3 & 0 & 0 & 0 \
0 & 2 & 0 & 0 \
0 & 0 & 1 & 0 \
endarray right]
$.
In this process I found $0$ is the only eigen value with algebraic multiplicity $4$ and geometric multiplicity $1$ so jordan canonical form should have only one 0-jordan block of order $4$.
But as $A^3 = 0$, we have $x^3$ as minimal polynomial and that suggest the largest $0$-jordan block can be of order $3$.
Please help, where am I wrong?
linear-algebra linear-transformations
I am trying to find the jordan canonical form of $
A=
left[ beginarraycccc
0 & 0 & 0 & 0 \
3 & 0 & 0 & 0 \
0 & 2 & 0 & 0 \
0 & 0 & 1 & 0 \
endarray right]
$.
In this process I found $0$ is the only eigen value with algebraic multiplicity $4$ and geometric multiplicity $1$ so jordan canonical form should have only one 0-jordan block of order $4$.
But as $A^3 = 0$, we have $x^3$ as minimal polynomial and that suggest the largest $0$-jordan block can be of order $3$.
Please help, where am I wrong?
linear-algebra linear-transformations
linear-algebra linear-transformations
edited Sep 1 at 8:23
Anonymous I
8311726
8311726
asked Sep 1 at 7:53
Voly op
354
354
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add a comment |Â
1 Answer
1
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octave:4> A
A =
0 0 0 0
3 0 0 0
0 2 0 0
0 0 1 0
octave:5> A^3
ans =
0 0 0 0
0 0 0 0
0 0 0 0
6 0 0 0
Notice at the lower left corner, the entry is non-zero. The minimal polynomial is indeed $x^4$.
Ohh .. I calculated A^4 directly instead of A^3 and thought it was A^3. Poor me. Thank you.
â Voly op
Sep 1 at 8:10
add a comment |Â
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
up vote
0
down vote
accepted
octave:4> A
A =
0 0 0 0
3 0 0 0
0 2 0 0
0 0 1 0
octave:5> A^3
ans =
0 0 0 0
0 0 0 0
0 0 0 0
6 0 0 0
Notice at the lower left corner, the entry is non-zero. The minimal polynomial is indeed $x^4$.
Ohh .. I calculated A^4 directly instead of A^3 and thought it was A^3. Poor me. Thank you.
â Voly op
Sep 1 at 8:10
add a comment |Â
up vote
0
down vote
accepted
octave:4> A
A =
0 0 0 0
3 0 0 0
0 2 0 0
0 0 1 0
octave:5> A^3
ans =
0 0 0 0
0 0 0 0
0 0 0 0
6 0 0 0
Notice at the lower left corner, the entry is non-zero. The minimal polynomial is indeed $x^4$.
Ohh .. I calculated A^4 directly instead of A^3 and thought it was A^3. Poor me. Thank you.
â Voly op
Sep 1 at 8:10
add a comment |Â
up vote
0
down vote
accepted
up vote
0
down vote
accepted
octave:4> A
A =
0 0 0 0
3 0 0 0
0 2 0 0
0 0 1 0
octave:5> A^3
ans =
0 0 0 0
0 0 0 0
0 0 0 0
6 0 0 0
Notice at the lower left corner, the entry is non-zero. The minimal polynomial is indeed $x^4$.
octave:4> A
A =
0 0 0 0
3 0 0 0
0 2 0 0
0 0 1 0
octave:5> A^3
ans =
0 0 0 0
0 0 0 0
0 0 0 0
6 0 0 0
Notice at the lower left corner, the entry is non-zero. The minimal polynomial is indeed $x^4$.
answered Sep 1 at 8:01
Siong Thye Goh
81.9k1456104
81.9k1456104
Ohh .. I calculated A^4 directly instead of A^3 and thought it was A^3. Poor me. Thank you.
â Voly op
Sep 1 at 8:10
add a comment |Â
Ohh .. I calculated A^4 directly instead of A^3 and thought it was A^3. Poor me. Thank you.
â Voly op
Sep 1 at 8:10
Ohh .. I calculated A^4 directly instead of A^3 and thought it was A^3. Poor me. Thank you.
â Voly op
Sep 1 at 8:10
Ohh .. I calculated A^4 directly instead of A^3 and thought it was A^3. Poor me. Thank you.
â Voly op
Sep 1 at 8:10
add a comment |Â
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