Page 121 - 35Linear Algebra
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7








                                                                                 Matrices






                   Matrices are a powerful tool for calculations involving linear transformations.
                   It is important to understand how to find the matrix of a linear transforma-
                   tion and the properties of matrices.




                   7.1     Linear Transformations and Matrices


                   Ordered, finite-dimensional, bases for vector spaces allows us to express linear
                   operators as matrices.



                   7.1.1    Basis Notation



                   A basis allows us to efficiently label arbitrary vectors in terms of column
                   vectors. Here is an example.

                   Example 74 Let

                                                    a  b
                                            V =             a, b, c, d ∈ R
                                                    c d
                   be the vector space of 2 × 2 real matrices, with addition and scalar multiplication
                   defined componentwise. One choice of basis is the ordered set (or list) of matrices



                                    1 0      0 1      0 0      0 0         1  1  2  2
                            B =           ,        ,        ,         =: (e , e , e , e ) .
                                                                                 1
                                                                                    2
                                                                           1
                                                                              2
                                    0 0      0 0      1 0      0 1
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