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 x 2              x 3
                                      
                                  y       C 1  dx   C 2     C 1 x   C   .  As  we  integrated
                                               
                                                                      2
                                        2                6
                                 twice, got two arbitrary constant, which noted  C  and C  .
                                                                               1      2
                                     Putting the set regional terms, we will form the system of
                                 two  equations  for  searching  for  of  arbitrary  constants:
                                 1
                                   C 1  C 2   ,0
                                 6
                                 
                                  4   2C  C  ;
                                       1   2
                                 3

                                                          7
                                      From where   C      and C     1 .
                                                     1            2
                                                          6
                                     Consequently, the partial decision of equation  y ''  x  after
                                                                                 x 3  7
                                 regional terms  1( y  )  , 0  ) 2 ( y    0 has a kind:  y    x    . 1
                                                                                  6   6
                                     The  unique  partial  decision  is  found  in  the  considered
                                 example, that satisfies regional terms. However  so will be not
                                 always. Can so happen, whatever   differential  Equation of  the
                                 second  order  will  have  partial  decision  after  regional  terms
                                  y (x  )   y  ,  y (x  )   y  or will have endless their amount. The
                                     1    1      2     2
                                 native  difference  of  setting  of  regional  terms  from  initial
                                 consists   herein.    If    the    set   initial   conditions
                                  y (x  )   y  , y (x  )   y   Cauchy  theorem  guarantees  put  task
                                     0    0      0    0
                                 will have the unique decision. If the set regional terms, finding
                                 the common decision, we will be able to set, whether the task of
                                 upshots has and how many.
                                     We  will  notice  that  not  always  the  common  decision  of
                                 differential equation of  the n-th  order  succeeds  to be  got  in  a
                                 kind (2.4). Mostly in the process of solving we get correlation of
                                 kind

                                     Ф(х, у, c 1,c 2,…,c n)=0,


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