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and               let              us               integrate:
                                  dy     dx     dy       dx                               C
                                          ,           ,  ln y      ln x  1   ln C  ,  y  
                                  y     x   1   y      x   1                           x   1

                                     The  common  decision  of  LNDE  was  got.  We  will  search
                                                                         C  x
                                 the  common  decision  of  LNDR  as  y      ,  where    xC    –
                                                                         x   1
                                 some function.
                                                                C   x  C  x
                                     We will find derivative   y    
                                                                 x   1   x   1  2

                                 and we will put  y  and  y  in LNDR:

                                      C   x  C  x  C  x  cos x
                                                                  .
                                      x   1   x   1  2   x   1  2  x   1

                                     We get equation  with  the  separated variables, which  after
                                 obvious simplifications acquires a kind
                                     C   x   cos  x ,
                                     from where
                                                   ~
                                     C  x   sin  x   C ,
                                                    ~
                                     where through C  the marked arbitrary became integration.
                                     We will get the common decision  of the given equation in a
                                           sin  Cx
                                 kind:  y          . 
                                             x   1

                                     2 Method of artificial replacement (Euler-Bernoulli method)

                                     Bernoulli suggested to search the upshots LNDE

                                                     y    P  yx    Q   x                                           (2.25)

                                 as work of two functions

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