Page 83 - 35Linear Algebra
P. 83

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                                                   Vectors in Space, n-Vectors






                   To continue our linear algebra journey, we must discuss n-vectors with an
                   arbitrarily large number of components. The simplest way to think about
                   these is as ordered lists of numbers,


                                                            
                                                          a 1
                                                           .
                                                   a =  .  .
                                                        . 
                                                          a n

                   Do not be confused by our use of a superscript to label components of a vector.
                         2
                   Here a denotes the second component of the vector a, rather than the number
                   a squared!
                      We emphasize that order matters:

                   Example 43 (Order of Components Matters)

                                                          
                                                     7       7
                                                     4
                                                             2
                                                          
                                                      6=    .
                                                     2       4
                                                          
                                                     5       5
                                                        n
                   The set of all n-vectors is denoted R . As an equation
                                                                   
                                                a   1
                                                                       
                                                                     
                                          n
                                                    .
                                        R :=      .    1       n       .
                                                  .  a , . . . , a ∈ R
                                                                     
                                                   a
                                                   n                  
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