Page 220 - Schaum's Outline of Differential Equations
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CHAP. 20]            SOLVING SECOND-ORDER   DIFFERENTIAL EQUATIONS                    203











































               Continuing in this manner, we generate Table 20-5.

                                                   Table 20-5

                                      Method:   RUNGE-KUTTA   METHOD
                                                 2
                                      Problem:  3x y" -xy'  + y = 0; y(l)  = 4, /(I) = 2
                                                ft = 0.2
                                 x n
                                                                  True  solution
                                           y n          •^n       Y(x)  = x + 3x 113
                                                        •7
                                 1.0    4.0000000    2.0000000      4.0000000

                                 1.2    4.3879715    1.8855447      4.3879757
                                 1.4    4.7560600    1.7990579      4.7560668

                                 1.6    5.1088123    1.7309980      5.1088213
                                 1.8    5.4493105    1.6757935      5.4493212

                                2.0     5.7797507    1.6299535      5.7797632


                                                           2
         20.10.  Use the Adams-Bashforth-Moulton method to solve 3.x )/' -  xy' + y = 0; y(l)  = 4, /(I) = 2 on the interval
               [1,2] with/; = 0.2.
                  It follows from  Problem 20.3, that/(^, y, z) = z, g(x, y, z) = (xz - y)/^),  X 0=l,y 0  = 4,andz 0 = 2. From Table 20-5,
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