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as
                                                   *
                                                           y   C 1 ( )x y   C 2 ( )x y ,                            (6.5)
                                                                       2
                                                             1

                                 where  C  ( )x  and  C  ( )x  are some functions which are subject
                                         1           2
                                 of  determination.  We  shall  show  that  these  functions  can  be
                                 found by operations of integration. Basic idea of this method -
                                 not that, how to guess, that the partial decision of heterogeneous
                                 Equation needs to be searched in a kind (6.5) and that in such
                                 kind he can be found.
                                     For  finding  of  two  functions  C  ( )x   and  C  ( )x   let  we
                                                                      1           2
                                 differentiate  (6.5):
                                                    *
                                                            y   C y   C y   (C y     C y   )
                                                         1 1    2  2   1 1    2  2
                                     On  a  function  C  ( )x and  C  ( )x   we  will  impose  an
                                                        1          2
                                 additional condition :
                                                                C y     C y     0.                                  (6.6)
                                                       1 1   2  2
                                     Then:
                                                        *
                                                       y   C y   C y ,
                                                              1 1   2  2
                                                 *
                                               y     C y  C y   (C y     C y  2  2 )  .
                                                             2
                                                               2
                                                                    1 1
                                                      1 1
                                                               *   *   *
                                     We put  the found values   y  , y  , y  in  (6.4):
                                                                                
                                 C  (y   а  y   а  y  ) C  (y   а  y   а  y  ) C  y   C  y   f  (x )
                                   1  1   1  1  2  1   2  2    1  2  2  2   1  1   2  2

                                     Expressions  in  the  first  and  second  handles  equal  a  zero
                                 (because  y   and   y  are  upshots  LHDE).
                                           1        2
                                     And we have therefore:

                                                                C y     C y     f  ( )x .                            (6.7)
                                                       1 1   2  2

                                     For  determination  C  , C   we  take  the  system  of  two
                                                          1   2
                                 equations (6.6) and (6.7):


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