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What is a column n-tuple?

  1. Aug 31, 2010 #1
    Yet another silly question from me :/. From an instructor's notes: "Let V = R^n be the vector space of column n-tuples of real numbers." Not quite sure what the "tuple" means. For R^3, would an example be the transpose of (1,2,3)?

    Thanks in advance for responding. While we're at it, any recommendations for online resources regarding dual spaces? These notes are a bit confusing.
     
  2. jcsd
  3. Aug 31, 2010 #2

    Office_Shredder

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    Yes, that's exactly what it is. An n-tuple is just a list of n numbers. So a 3-tuple would be something of the form (x,y,z) and a 4-tuple would be something of the form (w,x,y,z).
     
  4. Sep 1, 2010 #3

    HallsofIvy

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    A "column n-tuple" is simply an n-tuple written as a column. A column "3-tuple" would be somthing like
    [tex]\begin{bmatrix}1 \\ 2 \\ 3\end{bmatrix}[/tex]
    where a row "3-tuple" would be
    [tex]\begin{bmatrix}1 & 2 & 3\end{bmatrix}[/tex].

    The distinction is important when working with matrices. If A is an n by n matrix then "Av" is defined for v a column n-tuple while "vA" is define for v a row n-tuple.
     
  5. Sep 1, 2010 #4
    Thanks for the detailed explanation :).
     
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