Page 126 - Schaum's Outline of Differential Equations
P. 126

CHAP.  12]                      VARIATION OF PARAMETERS                               109



               Solving this set of equations simultaneously, we obtain




               whence


               Then,  from  (_/),



               and the general  solution is




                  The solution also can be obtained  simply by integrating both sides of the differential  equation four times with
               respect to x.




                                     Supplementary Problems


         Use variation of parameters  to find  the  general  solutions of the following differential  equations:










                           In x if two solkution to the associated homogeneous problem are known to be x and 1/x

                           if two solution to the associated homogeneous problem are known to be I andex2.











                                                                                              2
                                    if two solutions to the associated  homogeneous equations are known to be t and i  + 1.
         12.24.                             if two solutions to the associated  homogeneous  equations are known to be
                and






         12.29.          if  three  linearly independent  solutions to  the  associated  homogeneous  equations  are  known  to  be
                   and

                   4-y(3) _  32 g2*
         12.30. y(S) _
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