Page 128 - Engineering Mathematics Workbook_Final
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Differential Equations & Partial Differential Equations

            262.  The  curve  for  which  the  area  of  the      266.  In which of the following differential
                   triangle  formed  by  the  x-axis,  the               equation degree is not defined?
                   tangent lie at any point P and line OP                                   2
                                                                                                        2
                                                                               2
                                2
                   is equal to a  is                                     (a)   d y  +  3       dy          =  x log  d y
                                                                             dx 2       dx          dx 2
                                a 2
                                                        2
                                                   −
                   (a)  x cy=  +         (b)  y =  x cx                        2   2                   2 
                                 y                                             d y        dy     2    d y 
                                                                         (b)    dx 2   +    dx        =  x sin   dx 2 
                                                                                   
                                                                                                             
                                                                             
                                                                                                       
                                 a 2                  a 2                                                
                                               =
                         =
                   (c)  y cx +           (d)  x cy −                                          
                                 x                     y                               dy     
                                                                         (c)  x =  sin   dx  −  2y      , x  1
            263.  For  the  differential  equation  whose                                     
                                       )
                                                    2
                                        2
                   solution  is  (x h +     ( y k  ) =  a                                      dy   
                                               −
                                    −
                                                         2
                                                                         (d)  x −  2y =  log      
                   (a is a constant), its                                                    dx 
                   (a) order is 2        (b) order is 3           267.  y =   ae − 1/ x  +  b   is  a  solution  of
                   (c) degree is 2       (d) degree is 3                  dy  =  y  , then
                                                                          dx    x 2
                                                       +
                                             dy    ax h
            264.  The      solution    of        =
                                                       +
                                             dx    by k                  (a) a   R −    0
                   represents a parabola when
                                                                                 0
                                                                         (b) b =
                   (a) a =  0, b   0    (b) a   0, b   0
                                                                         (c) b = 1
                   (c) b =  0, a   0    (d) a =  0, b   R
                                                                         (d) a takes finite number of values

            265.  The  solution  of  the  differential            268.  Which of the following equation(s) is
                   equation  ( x y −    ) 1 dy +  2xy dx =               / are linear?
                                   2
                                 2
                                                   3
                                                         0
                   is                                                        dy    y
                                                                         (a)     +   =  log x
                   (a) 1 x y+  2  2  =  cx                                   dx    x
                                                                                   dy   
                        +
                   (b) 1 x y =  2  2  cy                                 (b)  y     dx        +  4x =  0

                           0
                   (c)  y =                                                              dy 
                                                                         (c) (2x +  y 3 )            =  3y
                              1                                                          dx 
                   (d)  y = −
                              x 2                                        (d) None of these







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