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Homework Help: Matrix question

  1. Feb 5, 2006 #1
    Hi

    I got a question regarding a matrix expression:

    Let [tex] X \in Mat_{n,n} (\mathbf{F}) [/tex]. Then I'm suppose to show AX = XA for all [tex]A \in Mat_{n,n} \mathbf{(F)}[/tex] if and only if [tex]s \in \mathbf{F}[/tex]

    What is the best way of going about this?

    /Fred
     
    Last edited: Feb 5, 2006
  2. jcsd
  3. Feb 5, 2006 #2

    HallsofIvy

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    Did you miswrite something? What matrix expression?
     
  4. Feb 6, 2006 #3
    No, It is correctly typed.

    /Fred

     
  5. Feb 6, 2006 #4

    matt grime

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    You did mistype something. s appears in the last three symbols and nowhere before, and the X vanishes from the question.
     
    Last edited: Feb 6, 2006
  6. Feb 6, 2006 #5

    HallsofIvy

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    When I first looked at it there was no matrix expression! May have been the server was slow in loading the LATEX. However, as Matt said, "if and only if [tex]s \in \mathbf{F}[/tex] makes no sense as there is no "s" in the hypothesis.
     
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