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P. 62

1                      3
                                       3                     (x   c  )
                                             3
                                      3   3y   x   c 2 ,  y   2  .
                                       2                       18

                                     From an initial condition у(1)=1 we find с 2:

                                     1   1 (  c  ) 3  / 18 , c    3  18   . 1
                                              2         2

                                     Consequently, the sought decision after part is determined
                                 by a formula
                                          1
                                      y    ( x  3  18   ) 1  3  . 
                                         18


                                     Exercises:

                                          1. To check or the indicated functions are the upshots of
                                 differential equations :
                                        1  2   1
                                 а)   y   x    x  ; y   y   x  .
                                        8      16
                                 б )   y   C e  1 C x  ; yy     'y  2  .
                                           2
                                          2. Find decision of equation:
                                      2
                                     d y                       2
                                 а)        y  ,     б)   xy   1 x  .
                                     dx 2
                                                             ln 'y
                                              2
                                 в)   xy   1 x  ,   г)   xy   ' y  .
                                                               x










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