Page 24 - Schaum's Outline of Differential Equations
P. 24

CHAP.1]                              BASIC CONCEPTS                                    7




         1.26.  Which  of  the following functions  are  solutions  of the  differential equation  y  — 2ty  =  f!
                                                              2
               (a)  y = 2,  (b)  y = -\,  (c)  y = e'\  (d)  y = e' -±,  (e)  y = -1/-\
         1.27.  Which of  the following functions are solutions of the differential  equation dyldt  = yltl
               (a)  y = 0,  (b)  y = 2,  (c)  y = 2t,  (d)  y = -3t,  (e)  y = t 2

         1.28.  Which  of the following functions  are solutions of the differential  equation









         1.29.  Which  of the following functions are solutions of the differential equation  y" -y  = 0?
                                                 x
               (a)  y = e",  (b)  y = sin x,  (c)  y = 4e ,  (d)  y = 0,
         1.30.  Which  of  the following functions  are  solutions  of the  differential equation  y"  — xy'  + y = Ql
                      2
                                                              2
                                                  2
               (a)  y = x ,  (b)  y = x,  (c)  y=l-x ,  (d)  y = 2x - 2,  (e)  y = 0
         1.31.  Which  of the following functions are solutions of the differential equation  x -  4x + 4x = e'
                                                             2
                                   2
                                                2t
                                                                          2t
               (a)  x = e',  (b)  x = e ',  (c)  x = e + e',  (d)  x=  te ' + e',  (e)  x = e + te'
                                                    2t
         In Problems  1.32 through  1.35, find  c so that x(t) = ce  satisfies the given initial  condition.
         1.32.  X0) = 0  1.33.  X0)=l  1.34.  XI) =1   1-35.  x(2) =  -3

         In Problems  1.36 through  1.39, hnd c so that y(x)  = c(\-  x)  satishes the given initial  condition.

         1.36.  XO) = 1  1-37.  XI) = 0  1.38.  y(2)  = 1  1.39.  XI) = 2

         In Problems  1.40 through  1.49, find c 1 and c 2 so that y(x)  = c 1 sin x + c 2 cos x will satisfy  the given  conditions
         Determine  whether the given conditions  are initial  conditions  or boundary  conditions.

         1.40.  XO) =  1,  /(O) = 2          1.41.  XO) = 2,  y'(0) = 1









                                             1.45.  XO) =  1,  Y(ri)  = 1



         1.46.  XO) =  1,  XTC) = 2          1.47.  XO) = 0,  /(O) = 0
   19   20   21   22   23   24   25   26   27   28   29