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                                SYSTEM OF LINEAR

                                                 EQUATIONS









            In this chapter, we deal with several numerical schemes for solving a system of
            equations
                                a 11 x 1 + a 12 x 2 +· · · + a 1N x N = b 1
                                a 21 x 1 + a 22 x 2 +· · · + a 2N x N = b 2
                                                                        (2.0.1a)
                                        .. ...... .     = .

                              a M1 x 1 + a M2 x 2 +· · · + a MN x N = b M
            which can be written in a compact form by using a matrix–vector notation as

                                        A M×N x = b                     (2.0.1b)

            where
                                                                      
                         a 11  a 12  ·  ·  a 1N          x 1            b 1
                         a 21  a 22
                                  ·  ·                                
              A M×N =                  a 2N   ,  x =    x 2  ,  b =    b 2 
                       ·      ·   ·  ·   ·            ·            · 
                        a M1  a M2  ·  · a MN            x N            b M
              We will deal with the three cases:

               (i) The case where the number (M) of equations and the number (N)of
                  unknowns are equal (M = N) so that the coefficient matrix A M×N is
                  square.

                                          
            Applied Numerical Methods Using MATLAB , by Yang, Cao, Chung, and Morris
            Copyright  2005 John Wiley & Sons, Inc., ISBN 0-471-69833-4
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