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Chapter 3. Linear Maps
                       62
                                                   Suppose n is a positive integer and a i,j ∈ F for i, j = 1,...,n.
                                              26.
                                                   Prove that the following are equivalent:
                                                   (a)   The trivial solution x 1 = ··· = x n = 0 is the only solution
                                                         to the homogeneous system of equations
                                                                              n

                                                                                a 1,k x k = 0
                                                                             k=1
                                                                                      . . .
                                                                              n

                                                                                a n,k x k = 0.
                                                                             k=1
                                                   (b)   For every c 1 ,...,c n ∈ F, there exists a solution to the sys-
                                                         tem of equations
                                                                             n

                                                                                a 1,k x k = c 1
                                                                             k=1
                                                                                     . . .

                                                                             n

                                                                               a n,k x k = c n .
                                                                            k=1

                                                   Note that here we have the same number of equations as vari-
                                                   ables.
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