Page 99 - Schaum's Outline of Differential Equations
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82                LINEAR  DIFFERENTIAL  EQUATIONS:  THEORY  OF SOLUTIONS         [CHAR  8



         8.55.  Prove  directly that the set given in Problem  8.49  is linearly  dependent.

         8.56.  Using the results of Problem  8.42,  construct  the general  solution of y" -4y = 0.

         8.57.  Using the results of Problem  8.43,  construct  the general  solution of y" -  5y' + 6y = 0.
         8.58.  What can one say about  the general  solution of y" + 16y = 0 if two particular  solutions are known  to be y 1 = sin 4x
               and y 2 = cos 4x1
                                                                                             8
         8.59.  What can one  say about  the  general  solution of y"  — Sy'  = 0 if two particular solutions are known  to be y^ = e * and
               3-2=1?
         8.60.  What  can one  say about  the  general  solution  of y" + y' = 0 if two particular  solutions  are  known  to be y 1 = 8 and
               y 2= 1?
         8.61.  What can one say about  the  general  solution of y'" -  y" = 0 if two particular  solutions are known  to be y± = x and
                   x
               y 2 = e ?
         8.62.  What can one say about  the general  solution of y"' + y" + y' + y = 0 if three particular solutions are known to be the
               functions  given in Problem  8.49?

         8.63.  What  can  one  say about  the  general  solution  of y'" — 2y"  — y' + 2y = 0if  three particular  solutions are known  to  be
               the functions  given in Problem  8.48?

         8.64.  What can one say about the general  solution of cfy/dx 5  = 0 if three particular solutions are known to be the  functions
               given in Problem  8.47?

         8.65.  Find the general  solution of y" + y = x , if one solution is y = x  -  2, and if two solutions of y" + y = 0 are sin x and
                                          2
                                                            2
               cos x.
                                                               2
                                           2
         8.66.  Find  the  general  solution  of  y"  — y = x ,  if  one  solution  is  y = —x  — 2,  and  if  two  solutions  of  y"  — y = 0  are  e*
               and 3e".
         8.67.  Find  the  general  solution  of  y'"  — y" — y'  + y  = 5,  if  one  solution  is  y = 5,  and  if  three  solutions  of  y'"  — y"
                              x
               — y'  + y = 0 are  e", e~ , and xe".
                                                                          2
         8.68.  The initial-value problem y' -  (2lx)y  = 0; y(0)  = 0 has two solutions y = 0 and y = x . Why doesn' t this result violate
               Theorem  8.1?

         8.69.  Does Theorem  8.1 apply to the initial-value problem y' -  (2/x)y  = 0; y(i)  = 3?
         8.70.  The  initial-value problem  xy'  — 2y = 0; y(0)  = 0 has two  solutions y = 0 and  y = x . Why  doesn't this result  violate
                                                                         2
               Theorem  8.1?
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