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 1                    * y   e 2x (Ax   ) B
                                                
                                       1     * y   2e  2x  (Ax   B ) e  2x  A   e  2x  2 ( Ax   2B   ) A
                                      2   * y     2e 2x  2 ( Ax   2B   A ) e  2x  2A   e 2x  4 ( Ax   4B   4A )
                                                    x
                                                   2
                                                                           x
                                                                          2
                                 2 y *    y *    y*   e ( 5 Ax 5  B 7  A)   4 xe

                                                       x
                                                      2
                                 let  us  simplify  on  e   and  equating  coefficients  at  identical
                                 degrees  x , we get
                                      x 1  5 A  4                   4        28
                                                    , from where  A    , B      .
                                      x 0  5 B  7 A  0             5        25

                                     Consequently,  the  partial  decision  LNDE  has  a  kind
                                          4    28 
                                   * y   e  2x   x     .
                                          5    25 

                                     Common decision of LNDE is
                                                            x
                                          ~          x      2  2x  4   28 
                                      y   y   *y   C  e   C  e   e   x     . 
                                                   1     2
                                                                   5    25 

                                     Example 6.6 To find the common decision of equation
                                                      x
                                      y    2 y    y   xe .

                                       We have LNDE with constant coefficients with right part
                                 of the special kind. According to LHDE we get

                                           y  2  y   y    0.

                                     We  make  characteristic  equation   2    2   1   0,  and
                                       1 .
                                   1   2
                                                                   ~
                                                                                  x
                                     Common decision of LHDE is  y    C (    C  x) e .
                                                                         1    2

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