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76      2 Nonlinear algebraic systems



                      2      initia ess       1   2   1 n er  iter  atins  11
                                       1

                      1


                      1

                     2










                     1
                                        2            2
                                               1
                   Figure 2.10 Trajectory of Newton’s method with the initial guess (1,1).


                               initia ess       2     1 n  er  iter  atins  21
                        2                 1    2


                       2





                     2
                      1

                      12
                      1
                      1

                      1
                                           2        1                   1
                                                 1
                   Figure 2.11 Trajectory of Newton’s method with the initial guess (2,−1).



                   certainly appears as if the choice of updates could be improved, by moderating the tendency
                   of the algorithm to make large, erratic steps. A reduced-step algorithm is proposed later
                   that avoids generating these erratic steps and makes Newton’s method more robust. These
                   plots are generated by Newton 2D test.m.
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