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Homework Help: Linear Algebra matrix help

  1. Jan 16, 2010 #1
    Im working on this problem and got stuck i would appreciate any help...

    Let Eij be the n × n matrix with 1 at the (i, j)th place and zero elsewhere.
    For a scalar c in K, put S = I + cEij . And let T be the n × n
    matrix obtained from the identity matrix as follows. In I replace 1 at
    the (i, i)th and (j, j)th entries by zero. Replace zeros at the (i, j)th and
    (j, i)th entry by 1. Suppose A is an n × n matrix. Compute SA, AS,
    TA, and AT to conclude what does the multiplication on the left or
    right by S or T do to the row or columns of A.

  2. jcsd
  3. Jan 16, 2010 #2


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    Welcome to PF!

    Hi robbie! Welcome to PF!: :smile:

    (try using the X2 tag just above the Reply box :wink:)

    Show us what you've tried, and where you're stuck, and then we'll know how to help! :smile:

    (if you want to write the matrices out, either use the CODE tag, 3 to the left of the X2 tag, or use LaTeX and http://www.physics.udel.edu/~dubois/lshort2e/node54.html#SECTION00830000000000000000" [Broken])
    Last edited by a moderator: May 4, 2017
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