Find a Matrix A on the ring of integers modulo 3 so that KerA=ImB.
up vote
0
down vote
favorite
B={{1,1,1},{0,1,2},{2,1,0},{0,2,2}}
I understand that each vector from then span of column vectors of B is a solution for Ax=o and that matrix A should have four columns. However I don't know how many rows it should have and how to find it.
linear-algebra matrices modular-arithmetic
add a comment |
up vote
0
down vote
favorite
B={{1,1,1},{0,1,2},{2,1,0},{0,2,2}}
I understand that each vector from then span of column vectors of B is a solution for Ax=o and that matrix A should have four columns. However I don't know how many rows it should have and how to find it.
linear-algebra matrices modular-arithmetic
add a comment |
up vote
0
down vote
favorite
up vote
0
down vote
favorite
B={{1,1,1},{0,1,2},{2,1,0},{0,2,2}}
I understand that each vector from then span of column vectors of B is a solution for Ax=o and that matrix A should have four columns. However I don't know how many rows it should have and how to find it.
linear-algebra matrices modular-arithmetic
B={{1,1,1},{0,1,2},{2,1,0},{0,2,2}}
I understand that each vector from then span of column vectors of B is a solution for Ax=o and that matrix A should have four columns. However I don't know how many rows it should have and how to find it.
linear-algebra matrices modular-arithmetic
linear-algebra matrices modular-arithmetic
asked Nov 17 at 10:02
Oleksandr
362
362
add a comment |
add a comment |
1 Answer
1
active
oldest
votes
up vote
1
down vote
Suppose $A$ has $r$ rows. As $mathbb Z_3$ is a field, by rank-nullity theorem,
$$
4 =text{dimension of domain of $A$}=operatorname{rank}(A)+operatorname{nullity}(A)=operatorname{rank}(A)+operatorname{rank}(B).
$$
Hence $r:=operatorname{rank}(A)=4-operatorname{rank}(B)$ and $A$ must have at least $r$ rows.
add a comment |
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
up vote
1
down vote
Suppose $A$ has $r$ rows. As $mathbb Z_3$ is a field, by rank-nullity theorem,
$$
4 =text{dimension of domain of $A$}=operatorname{rank}(A)+operatorname{nullity}(A)=operatorname{rank}(A)+operatorname{rank}(B).
$$
Hence $r:=operatorname{rank}(A)=4-operatorname{rank}(B)$ and $A$ must have at least $r$ rows.
add a comment |
up vote
1
down vote
Suppose $A$ has $r$ rows. As $mathbb Z_3$ is a field, by rank-nullity theorem,
$$
4 =text{dimension of domain of $A$}=operatorname{rank}(A)+operatorname{nullity}(A)=operatorname{rank}(A)+operatorname{rank}(B).
$$
Hence $r:=operatorname{rank}(A)=4-operatorname{rank}(B)$ and $A$ must have at least $r$ rows.
add a comment |
up vote
1
down vote
up vote
1
down vote
Suppose $A$ has $r$ rows. As $mathbb Z_3$ is a field, by rank-nullity theorem,
$$
4 =text{dimension of domain of $A$}=operatorname{rank}(A)+operatorname{nullity}(A)=operatorname{rank}(A)+operatorname{rank}(B).
$$
Hence $r:=operatorname{rank}(A)=4-operatorname{rank}(B)$ and $A$ must have at least $r$ rows.
Suppose $A$ has $r$ rows. As $mathbb Z_3$ is a field, by rank-nullity theorem,
$$
4 =text{dimension of domain of $A$}=operatorname{rank}(A)+operatorname{nullity}(A)=operatorname{rank}(A)+operatorname{rank}(B).
$$
Hence $r:=operatorname{rank}(A)=4-operatorname{rank}(B)$ and $A$ must have at least $r$ rows.
answered Nov 17 at 10:53
user1551
70.5k566125
70.5k566125
add a comment |
add a comment |
Thanks for contributing an answer to Mathematics Stack Exchange!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
Use MathJax to format equations. MathJax reference.
To learn more, see our tips on writing great answers.
Some of your past answers have not been well-received, and you're in danger of being blocked from answering.
Please pay close attention to the following guidance:
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fmath.stackexchange.com%2fquestions%2f3002156%2ffind-a-matrix-a-on-the-ring-of-integers-modulo-3-so-that-kera-imb%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown