Is a vector space a subspace of itself? The 2019 Stack Overflow Developer Survey Results Are In Announcing the arrival of Valued Associate #679: Cesar Manara Planned maintenance scheduled April 17/18, 2019 at 00:00UTC (8:00pm US/Eastern)vector space and its subspaceHow to determine vector space?Vector Space vs SubspaceProving a subset is a subspace of a Vector SpaceSubspace of a vector space DefinitionProof these operations is not a vector spaceVector Space definitionAre all vector spaces also a subspace?Understand the definition of a vector subspaceDoes multiplying by the zero vector ALWAYS yield the zero vector?

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Is a vector space a subspace of itself?



The 2019 Stack Overflow Developer Survey Results Are In
Announcing the arrival of Valued Associate #679: Cesar Manara
Planned maintenance scheduled April 17/18, 2019 at 00:00UTC (8:00pm US/Eastern)vector space and its subspaceHow to determine vector space?Vector Space vs SubspaceProving a subset is a subspace of a Vector SpaceSubspace of a vector space DefinitionProof these operations is not a vector spaceVector Space definitionAre all vector spaces also a subspace?Understand the definition of a vector subspaceDoes multiplying by the zero vector ALWAYS yield the zero vector?










3












$begingroup$


We know that a subspace is a vector space that follows the same addition and multiplication rules as $Bbb V$, but is a vector space a subspace of itself?
Also, I'm getting confused doing the practice questions, on when we prove that something is a vector space by using the subspace test and when we prove V1 - V10.



Edit: V1 - V10 are the ten axioms of what makes something a vector space. So for example in $Bbb R^2$, we have that $vecx + vecy = vecy + vec x$, etc..










share|cite|improve this question











$endgroup$







  • 1




    $begingroup$
    How do you define a subspace of a vector space?
    $endgroup$
    – Brian
    Apr 9 at 2:02






  • 3




    $begingroup$
    Is a set a subset of itself?? What’s V1-V10?
    $endgroup$
    – J. W. Tanner
    Apr 9 at 2:16







  • 2




    $begingroup$
    The term "proper" subspace is often used to denote a subspace space that is not the entire vector space.
    $endgroup$
    – Theo Bendit
    Apr 9 at 2:19






  • 4




    $begingroup$
    As other commenters have noted, your question lacks context. Please edit your question to include more context, lest your question be closed. Please give a definition of a subspace. Please explain what V1 - V10 means. If you are working from a particular text, a citation to that text would be helpful, too.
    $endgroup$
    – Xander Henderson
    Apr 9 at 3:39






  • 3




    $begingroup$
    @CompuChip That's not a usage of "proper set" that I'm accustomed to, but I can certainly imagine it being used by certain fields of maths. I would instead say "proper, non-trivial" to mean not the whole set/space, and not the empty set/$0$ subspace.
    $endgroup$
    – Theo Bendit
    Apr 9 at 8:57















3












$begingroup$


We know that a subspace is a vector space that follows the same addition and multiplication rules as $Bbb V$, but is a vector space a subspace of itself?
Also, I'm getting confused doing the practice questions, on when we prove that something is a vector space by using the subspace test and when we prove V1 - V10.



Edit: V1 - V10 are the ten axioms of what makes something a vector space. So for example in $Bbb R^2$, we have that $vecx + vecy = vecy + vec x$, etc..










share|cite|improve this question











$endgroup$







  • 1




    $begingroup$
    How do you define a subspace of a vector space?
    $endgroup$
    – Brian
    Apr 9 at 2:02






  • 3




    $begingroup$
    Is a set a subset of itself?? What’s V1-V10?
    $endgroup$
    – J. W. Tanner
    Apr 9 at 2:16







  • 2




    $begingroup$
    The term "proper" subspace is often used to denote a subspace space that is not the entire vector space.
    $endgroup$
    – Theo Bendit
    Apr 9 at 2:19






  • 4




    $begingroup$
    As other commenters have noted, your question lacks context. Please edit your question to include more context, lest your question be closed. Please give a definition of a subspace. Please explain what V1 - V10 means. If you are working from a particular text, a citation to that text would be helpful, too.
    $endgroup$
    – Xander Henderson
    Apr 9 at 3:39






  • 3




    $begingroup$
    @CompuChip That's not a usage of "proper set" that I'm accustomed to, but I can certainly imagine it being used by certain fields of maths. I would instead say "proper, non-trivial" to mean not the whole set/space, and not the empty set/$0$ subspace.
    $endgroup$
    – Theo Bendit
    Apr 9 at 8:57













3












3








3


1



$begingroup$


We know that a subspace is a vector space that follows the same addition and multiplication rules as $Bbb V$, but is a vector space a subspace of itself?
Also, I'm getting confused doing the practice questions, on when we prove that something is a vector space by using the subspace test and when we prove V1 - V10.



Edit: V1 - V10 are the ten axioms of what makes something a vector space. So for example in $Bbb R^2$, we have that $vecx + vecy = vecy + vec x$, etc..










share|cite|improve this question











$endgroup$




We know that a subspace is a vector space that follows the same addition and multiplication rules as $Bbb V$, but is a vector space a subspace of itself?
Also, I'm getting confused doing the practice questions, on when we prove that something is a vector space by using the subspace test and when we prove V1 - V10.



Edit: V1 - V10 are the ten axioms of what makes something a vector space. So for example in $Bbb R^2$, we have that $vecx + vecy = vecy + vec x$, etc..







linear-algebra vector-spaces






share|cite|improve this question















share|cite|improve this question













share|cite|improve this question




share|cite|improve this question








edited Apr 9 at 16:40







ming

















asked Apr 9 at 1:59









mingming

4606




4606







  • 1




    $begingroup$
    How do you define a subspace of a vector space?
    $endgroup$
    – Brian
    Apr 9 at 2:02






  • 3




    $begingroup$
    Is a set a subset of itself?? What’s V1-V10?
    $endgroup$
    – J. W. Tanner
    Apr 9 at 2:16







  • 2




    $begingroup$
    The term "proper" subspace is often used to denote a subspace space that is not the entire vector space.
    $endgroup$
    – Theo Bendit
    Apr 9 at 2:19






  • 4




    $begingroup$
    As other commenters have noted, your question lacks context. Please edit your question to include more context, lest your question be closed. Please give a definition of a subspace. Please explain what V1 - V10 means. If you are working from a particular text, a citation to that text would be helpful, too.
    $endgroup$
    – Xander Henderson
    Apr 9 at 3:39






  • 3




    $begingroup$
    @CompuChip That's not a usage of "proper set" that I'm accustomed to, but I can certainly imagine it being used by certain fields of maths. I would instead say "proper, non-trivial" to mean not the whole set/space, and not the empty set/$0$ subspace.
    $endgroup$
    – Theo Bendit
    Apr 9 at 8:57












  • 1




    $begingroup$
    How do you define a subspace of a vector space?
    $endgroup$
    – Brian
    Apr 9 at 2:02






  • 3




    $begingroup$
    Is a set a subset of itself?? What’s V1-V10?
    $endgroup$
    – J. W. Tanner
    Apr 9 at 2:16







  • 2




    $begingroup$
    The term "proper" subspace is often used to denote a subspace space that is not the entire vector space.
    $endgroup$
    – Theo Bendit
    Apr 9 at 2:19






  • 4




    $begingroup$
    As other commenters have noted, your question lacks context. Please edit your question to include more context, lest your question be closed. Please give a definition of a subspace. Please explain what V1 - V10 means. If you are working from a particular text, a citation to that text would be helpful, too.
    $endgroup$
    – Xander Henderson
    Apr 9 at 3:39






  • 3




    $begingroup$
    @CompuChip That's not a usage of "proper set" that I'm accustomed to, but I can certainly imagine it being used by certain fields of maths. I would instead say "proper, non-trivial" to mean not the whole set/space, and not the empty set/$0$ subspace.
    $endgroup$
    – Theo Bendit
    Apr 9 at 8:57







1




1




$begingroup$
How do you define a subspace of a vector space?
$endgroup$
– Brian
Apr 9 at 2:02




$begingroup$
How do you define a subspace of a vector space?
$endgroup$
– Brian
Apr 9 at 2:02




3




3




$begingroup$
Is a set a subset of itself?? What’s V1-V10?
$endgroup$
– J. W. Tanner
Apr 9 at 2:16





$begingroup$
Is a set a subset of itself?? What’s V1-V10?
$endgroup$
– J. W. Tanner
Apr 9 at 2:16





2




2




$begingroup$
The term "proper" subspace is often used to denote a subspace space that is not the entire vector space.
$endgroup$
– Theo Bendit
Apr 9 at 2:19




$begingroup$
The term "proper" subspace is often used to denote a subspace space that is not the entire vector space.
$endgroup$
– Theo Bendit
Apr 9 at 2:19




4




4




$begingroup$
As other commenters have noted, your question lacks context. Please edit your question to include more context, lest your question be closed. Please give a definition of a subspace. Please explain what V1 - V10 means. If you are working from a particular text, a citation to that text would be helpful, too.
$endgroup$
– Xander Henderson
Apr 9 at 3:39




$begingroup$
As other commenters have noted, your question lacks context. Please edit your question to include more context, lest your question be closed. Please give a definition of a subspace. Please explain what V1 - V10 means. If you are working from a particular text, a citation to that text would be helpful, too.
$endgroup$
– Xander Henderson
Apr 9 at 3:39




3




3




$begingroup$
@CompuChip That's not a usage of "proper set" that I'm accustomed to, but I can certainly imagine it being used by certain fields of maths. I would instead say "proper, non-trivial" to mean not the whole set/space, and not the empty set/$0$ subspace.
$endgroup$
– Theo Bendit
Apr 9 at 8:57




$begingroup$
@CompuChip That's not a usage of "proper set" that I'm accustomed to, but I can certainly imagine it being used by certain fields of maths. I would instead say "proper, non-trivial" to mean not the whole set/space, and not the empty set/$0$ subspace.
$endgroup$
– Theo Bendit
Apr 9 at 8:57










2 Answers
2






active

oldest

votes


















5












$begingroup$

I'm guessing that V1 - V10 are the axioms for proving vector spaces.



To prove something is a vector space, independent of any other vector spaces you know of, you are required to prove all of the axioms in the definition. Not all operations that call themselves $+$ are worthy addition operations; just because you denote it $+$ does not mean it is (for example) associative, or has an additive identity.



There is a lot to prove, because there's a lot to gain. Vector spaces have a simply enormous amount of structure, and that structure gives us a really rich theory and powerful tools. If you have an object that you wish to understand better, and you can show it is a vector space (or at least, related to a vector space), then you'll instantly have some serious mathematical firepower at your fingertips.



Subspaces give us a shortcut to proving a vector space. If you have a subset of a known vector space, then you can prove just $3$ properties, rather than $10$. We can skip a lot of the steps because somebody has already done them previously when showing the larger vector space is indeed a vector space. You don't need to show, for example, $v + w = w + v$ for all $v, w$ in your subset, because we already know this is true for all vectors in the larger vector space.



I'm writing this, not as a direct answer to your question (which Jose Carlos Santos has answered already), but because confusion like this often stems from some sloppiness on the above point. I've seen many students (and, lamentably, several instructors) fail to grasp that showing the subspace conditions on a set that is not clearly a subset of a known vector space does not prove a vector space. The shortcut works because somebody has already established most of the axioms beforehand, but if this is not true, then the argument is a fallacy.



You can absolutely apply the subspace conditions on the whole of a vector space provided you've proven it's a vector space already with axioms V1 - V10.






share|cite|improve this answer









$endgroup$








  • 1




    $begingroup$
    Ohh okay I think I understand. So when we prove that something is a subspace of say $Bbb R^2$, we don't have to prove that $c(vecx + vecy) = cvecx + cvecy$ because we already know that's true inside of $Bbb R^2$ and we know this subspace is a vector space INSIDE of $Bbb R^2$ following all its rules.
    $endgroup$
    – ming
    Apr 9 at 16:37







  • 1




    $begingroup$
    But then for questions like "A sequence is a infinite list of real numbers. For example 1, 2, 3, 4, 5 is a sequence, and so is 1, -1, 2, -2, 4, -4. We define addition and scalar multiplication so that...." We actually don't have any known information/facts about this vector space so then we need to prove all ten axioms?
    $endgroup$
    – ming
    Apr 9 at 16:39










  • $begingroup$
    @ming Exactly. Couldn't put it better myself.
    $endgroup$
    – Theo Bendit
    2 days ago


















11












$begingroup$

Yes, every vector space is a vector subspace of itself, since it is a non-empty subset of itself which is closed with respect to addition and with respect to product by scalars.






share|cite|improve this answer









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    2 Answers
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    active

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    2 Answers
    2






    active

    oldest

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    active

    oldest

    votes






    active

    oldest

    votes









    5












    $begingroup$

    I'm guessing that V1 - V10 are the axioms for proving vector spaces.



    To prove something is a vector space, independent of any other vector spaces you know of, you are required to prove all of the axioms in the definition. Not all operations that call themselves $+$ are worthy addition operations; just because you denote it $+$ does not mean it is (for example) associative, or has an additive identity.



    There is a lot to prove, because there's a lot to gain. Vector spaces have a simply enormous amount of structure, and that structure gives us a really rich theory and powerful tools. If you have an object that you wish to understand better, and you can show it is a vector space (or at least, related to a vector space), then you'll instantly have some serious mathematical firepower at your fingertips.



    Subspaces give us a shortcut to proving a vector space. If you have a subset of a known vector space, then you can prove just $3$ properties, rather than $10$. We can skip a lot of the steps because somebody has already done them previously when showing the larger vector space is indeed a vector space. You don't need to show, for example, $v + w = w + v$ for all $v, w$ in your subset, because we already know this is true for all vectors in the larger vector space.



    I'm writing this, not as a direct answer to your question (which Jose Carlos Santos has answered already), but because confusion like this often stems from some sloppiness on the above point. I've seen many students (and, lamentably, several instructors) fail to grasp that showing the subspace conditions on a set that is not clearly a subset of a known vector space does not prove a vector space. The shortcut works because somebody has already established most of the axioms beforehand, but if this is not true, then the argument is a fallacy.



    You can absolutely apply the subspace conditions on the whole of a vector space provided you've proven it's a vector space already with axioms V1 - V10.






    share|cite|improve this answer









    $endgroup$








    • 1




      $begingroup$
      Ohh okay I think I understand. So when we prove that something is a subspace of say $Bbb R^2$, we don't have to prove that $c(vecx + vecy) = cvecx + cvecy$ because we already know that's true inside of $Bbb R^2$ and we know this subspace is a vector space INSIDE of $Bbb R^2$ following all its rules.
      $endgroup$
      – ming
      Apr 9 at 16:37







    • 1




      $begingroup$
      But then for questions like "A sequence is a infinite list of real numbers. For example 1, 2, 3, 4, 5 is a sequence, and so is 1, -1, 2, -2, 4, -4. We define addition and scalar multiplication so that...." We actually don't have any known information/facts about this vector space so then we need to prove all ten axioms?
      $endgroup$
      – ming
      Apr 9 at 16:39










    • $begingroup$
      @ming Exactly. Couldn't put it better myself.
      $endgroup$
      – Theo Bendit
      2 days ago















    5












    $begingroup$

    I'm guessing that V1 - V10 are the axioms for proving vector spaces.



    To prove something is a vector space, independent of any other vector spaces you know of, you are required to prove all of the axioms in the definition. Not all operations that call themselves $+$ are worthy addition operations; just because you denote it $+$ does not mean it is (for example) associative, or has an additive identity.



    There is a lot to prove, because there's a lot to gain. Vector spaces have a simply enormous amount of structure, and that structure gives us a really rich theory and powerful tools. If you have an object that you wish to understand better, and you can show it is a vector space (or at least, related to a vector space), then you'll instantly have some serious mathematical firepower at your fingertips.



    Subspaces give us a shortcut to proving a vector space. If you have a subset of a known vector space, then you can prove just $3$ properties, rather than $10$. We can skip a lot of the steps because somebody has already done them previously when showing the larger vector space is indeed a vector space. You don't need to show, for example, $v + w = w + v$ for all $v, w$ in your subset, because we already know this is true for all vectors in the larger vector space.



    I'm writing this, not as a direct answer to your question (which Jose Carlos Santos has answered already), but because confusion like this often stems from some sloppiness on the above point. I've seen many students (and, lamentably, several instructors) fail to grasp that showing the subspace conditions on a set that is not clearly a subset of a known vector space does not prove a vector space. The shortcut works because somebody has already established most of the axioms beforehand, but if this is not true, then the argument is a fallacy.



    You can absolutely apply the subspace conditions on the whole of a vector space provided you've proven it's a vector space already with axioms V1 - V10.






    share|cite|improve this answer









    $endgroup$








    • 1




      $begingroup$
      Ohh okay I think I understand. So when we prove that something is a subspace of say $Bbb R^2$, we don't have to prove that $c(vecx + vecy) = cvecx + cvecy$ because we already know that's true inside of $Bbb R^2$ and we know this subspace is a vector space INSIDE of $Bbb R^2$ following all its rules.
      $endgroup$
      – ming
      Apr 9 at 16:37







    • 1




      $begingroup$
      But then for questions like "A sequence is a infinite list of real numbers. For example 1, 2, 3, 4, 5 is a sequence, and so is 1, -1, 2, -2, 4, -4. We define addition and scalar multiplication so that...." We actually don't have any known information/facts about this vector space so then we need to prove all ten axioms?
      $endgroup$
      – ming
      Apr 9 at 16:39










    • $begingroup$
      @ming Exactly. Couldn't put it better myself.
      $endgroup$
      – Theo Bendit
      2 days ago













    5












    5








    5





    $begingroup$

    I'm guessing that V1 - V10 are the axioms for proving vector spaces.



    To prove something is a vector space, independent of any other vector spaces you know of, you are required to prove all of the axioms in the definition. Not all operations that call themselves $+$ are worthy addition operations; just because you denote it $+$ does not mean it is (for example) associative, or has an additive identity.



    There is a lot to prove, because there's a lot to gain. Vector spaces have a simply enormous amount of structure, and that structure gives us a really rich theory and powerful tools. If you have an object that you wish to understand better, and you can show it is a vector space (or at least, related to a vector space), then you'll instantly have some serious mathematical firepower at your fingertips.



    Subspaces give us a shortcut to proving a vector space. If you have a subset of a known vector space, then you can prove just $3$ properties, rather than $10$. We can skip a lot of the steps because somebody has already done them previously when showing the larger vector space is indeed a vector space. You don't need to show, for example, $v + w = w + v$ for all $v, w$ in your subset, because we already know this is true for all vectors in the larger vector space.



    I'm writing this, not as a direct answer to your question (which Jose Carlos Santos has answered already), but because confusion like this often stems from some sloppiness on the above point. I've seen many students (and, lamentably, several instructors) fail to grasp that showing the subspace conditions on a set that is not clearly a subset of a known vector space does not prove a vector space. The shortcut works because somebody has already established most of the axioms beforehand, but if this is not true, then the argument is a fallacy.



    You can absolutely apply the subspace conditions on the whole of a vector space provided you've proven it's a vector space already with axioms V1 - V10.






    share|cite|improve this answer









    $endgroup$



    I'm guessing that V1 - V10 are the axioms for proving vector spaces.



    To prove something is a vector space, independent of any other vector spaces you know of, you are required to prove all of the axioms in the definition. Not all operations that call themselves $+$ are worthy addition operations; just because you denote it $+$ does not mean it is (for example) associative, or has an additive identity.



    There is a lot to prove, because there's a lot to gain. Vector spaces have a simply enormous amount of structure, and that structure gives us a really rich theory and powerful tools. If you have an object that you wish to understand better, and you can show it is a vector space (or at least, related to a vector space), then you'll instantly have some serious mathematical firepower at your fingertips.



    Subspaces give us a shortcut to proving a vector space. If you have a subset of a known vector space, then you can prove just $3$ properties, rather than $10$. We can skip a lot of the steps because somebody has already done them previously when showing the larger vector space is indeed a vector space. You don't need to show, for example, $v + w = w + v$ for all $v, w$ in your subset, because we already know this is true for all vectors in the larger vector space.



    I'm writing this, not as a direct answer to your question (which Jose Carlos Santos has answered already), but because confusion like this often stems from some sloppiness on the above point. I've seen many students (and, lamentably, several instructors) fail to grasp that showing the subspace conditions on a set that is not clearly a subset of a known vector space does not prove a vector space. The shortcut works because somebody has already established most of the axioms beforehand, but if this is not true, then the argument is a fallacy.



    You can absolutely apply the subspace conditions on the whole of a vector space provided you've proven it's a vector space already with axioms V1 - V10.







    share|cite|improve this answer












    share|cite|improve this answer



    share|cite|improve this answer










    answered Apr 9 at 2:54









    Theo BenditTheo Bendit

    20.9k12355




    20.9k12355







    • 1




      $begingroup$
      Ohh okay I think I understand. So when we prove that something is a subspace of say $Bbb R^2$, we don't have to prove that $c(vecx + vecy) = cvecx + cvecy$ because we already know that's true inside of $Bbb R^2$ and we know this subspace is a vector space INSIDE of $Bbb R^2$ following all its rules.
      $endgroup$
      – ming
      Apr 9 at 16:37







    • 1




      $begingroup$
      But then for questions like "A sequence is a infinite list of real numbers. For example 1, 2, 3, 4, 5 is a sequence, and so is 1, -1, 2, -2, 4, -4. We define addition and scalar multiplication so that...." We actually don't have any known information/facts about this vector space so then we need to prove all ten axioms?
      $endgroup$
      – ming
      Apr 9 at 16:39










    • $begingroup$
      @ming Exactly. Couldn't put it better myself.
      $endgroup$
      – Theo Bendit
      2 days ago












    • 1




      $begingroup$
      Ohh okay I think I understand. So when we prove that something is a subspace of say $Bbb R^2$, we don't have to prove that $c(vecx + vecy) = cvecx + cvecy$ because we already know that's true inside of $Bbb R^2$ and we know this subspace is a vector space INSIDE of $Bbb R^2$ following all its rules.
      $endgroup$
      – ming
      Apr 9 at 16:37







    • 1




      $begingroup$
      But then for questions like "A sequence is a infinite list of real numbers. For example 1, 2, 3, 4, 5 is a sequence, and so is 1, -1, 2, -2, 4, -4. We define addition and scalar multiplication so that...." We actually don't have any known information/facts about this vector space so then we need to prove all ten axioms?
      $endgroup$
      – ming
      Apr 9 at 16:39










    • $begingroup$
      @ming Exactly. Couldn't put it better myself.
      $endgroup$
      – Theo Bendit
      2 days ago







    1




    1




    $begingroup$
    Ohh okay I think I understand. So when we prove that something is a subspace of say $Bbb R^2$, we don't have to prove that $c(vecx + vecy) = cvecx + cvecy$ because we already know that's true inside of $Bbb R^2$ and we know this subspace is a vector space INSIDE of $Bbb R^2$ following all its rules.
    $endgroup$
    – ming
    Apr 9 at 16:37





    $begingroup$
    Ohh okay I think I understand. So when we prove that something is a subspace of say $Bbb R^2$, we don't have to prove that $c(vecx + vecy) = cvecx + cvecy$ because we already know that's true inside of $Bbb R^2$ and we know this subspace is a vector space INSIDE of $Bbb R^2$ following all its rules.
    $endgroup$
    – ming
    Apr 9 at 16:37





    1




    1




    $begingroup$
    But then for questions like "A sequence is a infinite list of real numbers. For example 1, 2, 3, 4, 5 is a sequence, and so is 1, -1, 2, -2, 4, -4. We define addition and scalar multiplication so that...." We actually don't have any known information/facts about this vector space so then we need to prove all ten axioms?
    $endgroup$
    – ming
    Apr 9 at 16:39




    $begingroup$
    But then for questions like "A sequence is a infinite list of real numbers. For example 1, 2, 3, 4, 5 is a sequence, and so is 1, -1, 2, -2, 4, -4. We define addition and scalar multiplication so that...." We actually don't have any known information/facts about this vector space so then we need to prove all ten axioms?
    $endgroup$
    – ming
    Apr 9 at 16:39












    $begingroup$
    @ming Exactly. Couldn't put it better myself.
    $endgroup$
    – Theo Bendit
    2 days ago




    $begingroup$
    @ming Exactly. Couldn't put it better myself.
    $endgroup$
    – Theo Bendit
    2 days ago











    11












    $begingroup$

    Yes, every vector space is a vector subspace of itself, since it is a non-empty subset of itself which is closed with respect to addition and with respect to product by scalars.






    share|cite|improve this answer









    $endgroup$

















      11












      $begingroup$

      Yes, every vector space is a vector subspace of itself, since it is a non-empty subset of itself which is closed with respect to addition and with respect to product by scalars.






      share|cite|improve this answer









      $endgroup$















        11












        11








        11





        $begingroup$

        Yes, every vector space is a vector subspace of itself, since it is a non-empty subset of itself which is closed with respect to addition and with respect to product by scalars.






        share|cite|improve this answer









        $endgroup$



        Yes, every vector space is a vector subspace of itself, since it is a non-empty subset of itself which is closed with respect to addition and with respect to product by scalars.







        share|cite|improve this answer












        share|cite|improve this answer



        share|cite|improve this answer










        answered Apr 9 at 2:06









        José Carlos SantosJosé Carlos Santos

        174k23133243




        174k23133243



























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