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Learn about matrices

  1. May 6, 2007 #1
    Iv just started (today is my first day)to learn about matrices. Now in my book it give's some practice problems and one I cant seem to get right. Can anyone here help me?
    Here is the problem..
    Now the answer SHOULD be(according to the book)
    But this is what I keep getting

    You see, Im right... up untill I have to subtract that -3...Any thoughts?
  2. jcsd
  3. May 6, 2007 #2


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    Well.. you may need to show some working. For example, the bottom left element has values i=3, j=1. So plug these into your equation-- what do you get?
  4. May 6, 2007 #3
    Yeah thats what I thought I was supposed to do..but when I do that I get:

    a31= 3^2+2(1)-3=5

    See what Im say'n?
  5. May 6, 2007 #4

    How do you get that?
  6. May 6, 2007 #5
    :approve: haha woops...I see what I did..thanks man:biggrin:
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