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Homework Help: Singular matrix

  1. Mar 14, 2005 #1
    Determine all values for x for which the
    matrix B =

    | x 3 -1|
    |9/2 x 3|
    | -2 1 1|

    No idea where to start. Any help?
     
  2. jcsd
  3. Mar 14, 2005 #2

    SpaceTiger

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    You mean the values for which it's singular? Do you know how to take a determinant?
     
  4. Mar 15, 2005 #3

    dextercioby

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    Why compute the determinant ???Do you know the condition a matrix must fulfil,in order to be singular...?

    Daniel.
     
  5. Mar 15, 2005 #4

    Galileo

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    It is singular precisely when its determinant is zero.
     
  6. Mar 15, 2005 #5

    dextercioby

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    I had a hunch you knew that,Galileo.I was just hoping that the OP would check the theory before attempting to solve the problem.

    Daniel.
     
  7. Mar 15, 2005 #6
    Figured it out. Just got the determinent and used quadratic equation to see when x=9 and x=-4, the matrix is singular
     
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