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P. 74

y
                                      y     0.
                                           x
                                     We  lower  his  order  by  replacement y    p  , y   p.
                                 Obsessed :
                                                      dp   p
                                                              0 ,
                                                      dy   x
                                                      dp   dx
                                                               0 ,
                                                       p    x

                                                      ln p   ln x   ln C  ,

                                                            p   Cx  ,

                                     from where, taking into account replacement, we reach :
                                       dy                          C   2    
                                           Cx   dy   Cxdx     y   x   C 1   ,
                                               
                                       dx                           2       
                                     that is
                                                           C
                                      
                                             2
                                      y   C x   C  , C   1  .
                                           2      1    2
                                                           2
                                     Consequently, the common  decision of the set equation  is
                                                  2
                                           3
                                      y   x   C x   C  .
                                               2      1
                                     On the basis of theorem 6 it is possible to do a conclusion
                                 that for finding of general decision LHDE (4.2) it is enough to
                                 find  his  fundamental  system  of  decisions  and  write  down
                                 general decision in a kind (4.12).   

                                     Exercises:

                                          1. To make  LHDE  after  the set of fundamental system
                                 of his decisions :
                                                                    ;
                                               а)   1 ; cos x            б)  x e x   .
                                                        ;
                                          2.  To  find  the common  decision  LHDE,  knowing him
                                 one decision :

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