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Homework Help: Mulitplying a matrice

  1. Sep 2, 2005 #1
    I understand the number of rows must equal the number of columns to multiply but:

    Is it possible to find the product of this matrice?

    AB if A= 0.....9..... -6
    ........ -2....-10......7

    B= 7
    ....5
    ...-2
     
  2. jcsd
  3. Sep 2, 2005 #2

    Galileo

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    Homework Helper

    Yes, you can multiply a 2x3 matrix with a 3x1 matrix. The result will be a 2x1 matrix.

    In general, you can only multiply a axb matrix with cxd matrix if b=c. The result is an axd matrix.
     
  4. Sep 2, 2005 #3
    Just so I have this straight:
    (0)(7) + (9)(5) + (-6)(-2) = 57
    (-2)(7) + (-10)(5) + (7)(-2) = -78

    written:
    57
    -78

    am I correct?
     
  5. Sep 2, 2005 #4
    or is it written: [57,-78] ?
     
  6. Sep 2, 2005 #5
    You can write it either way. Vertically, like you had it. Or horiz. with a T above the right parenthase. That is to indicate it is the transpose.
     
  7. Sep 2, 2005 #6
    Thank you very much!
     
  8. Sep 2, 2005 #7

    HallsofIvy

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    By the way- the singular of "matrices" is "matrix", not "matrice".
     
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