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25 | P a g e

                                                                         1   3 
                                                             p  2  1           4    5 
                       (b)    Find the values of p and q, if            2   1          .
                                                             3 0   q             11  19 
                                                                          4   5   



                                                  2
                                             3
               21.     (a)    Given matrix  B  B   6B  where B is a 3 3 matrix and I is a 3 3  identity
                                                          I
                              matrix.
                                                                               
                                                -1
                                                                                    2
                                                                               1
                                                                                       B
                              (i)    By using B onto the equation, show that  B   B     6 .
                                                                                            I

                                                     1   2  1
                                                              
                                                                            -1
                              (ii)   Hence , if   B       1   1 0 , determine B .
                                                              
                                                     3      1
                                                        1    
                        (b)   A system linear equations is given as follows.
                                                    3x  6y  3z  1
                                                    3x  3y      2
                                                    9x  3y  3z  1


                             (i)   Write the above system of linear equations in the form of  3BX  C  where B

                                   is the matrix from (a) (ii) above, X is an unknown column matrix and C is a

                                   constant column matrix.


                             (ii)    Hence,  by  using  the  inverse  matrix,  solve  the  above  system  of  linear

                                     equations.




                                          2   0            2  4
                                               
               22.     (a)    Given  B       0  4 , and  C       1  3     , find Y such that YC=B.
                                               
                                           5    1  


                                                                        0  2  T  6 1 
                                                                      
                                                                  T
                       (b)    Find the transpose matrix,    A  if3A  2  5 2          2    .
                                                           T
                                                                      
                                                                          1  3      2 2  6  
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