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P. 52

Example 3.1  To find the common decision of equation
                                              8
                                      y  IY       .
                                           ( x  ) 3  5

                                        Pursuant to a formula (1.6) and rules of integration, we
                                        have
                                                       8dx          2      ~
                                           
                                          y   y IY  dx            .c
                                                                           1
                                                     (x   )3  5  (x   )3  4

                                     We find farther
                                                           2      ~          2      ~    ~
                                            
                                         y   y     dx       (   c 1 )dx     xc 1   c 2 .
                                                        (x   )3  4       ( 3 x   )3  3

                                     Let us integrate last equality one more and we will get the
                                 common decision of the given differential equation:

                                                                                ~  2
                                                   2     ~    ~           1     c  x  ~    ~
                                    y   y   dx   (   xc 1   c 2 )dx        1   c 2 x   c 3 ,
                                     
                                             
                                                ( 3 x   )3  3         (x   )3  2  2
                                                                   ~  2
                                                            1      c  x  ~     ~
                                             
                                         y   y dx       (     1   c 2 x   c ) dx  
                                                                                3
                                                          x (   )3  2  2
                                                           ~  3  ~   2
                                                    1      c  x  c  x   ~    ~
                                                          1    2     c 3 x   c 4 .
                                                  ( 3 x   ) 3  6  2


                                     Arbitrary  constant  it  is possible remark for  more  compact
                                 record.  Then  the  sought  common  decision  after  will  collect  a
                                              1
                                                                2
                                                        3
                                 kind:  y           c 1 x   с 2 x   c 3 x   c 4 . 
                                            ( 3 x   ) 3



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