Page 146 - Engineering Mathematics Workbook_Final
P. 146

Complex Variables
                                                                                         +
                                                                                      −
            63.    Let C be the contour  z =  oriented                   initial point  1 2i and final point
                                              2
                                                                                                    +
                   in the anti-clockwise direction. The                  1 2i. The value of      C   1 2z  dz =
                                                                           +
                                                                                                     +
                                                3/z
                   value of the integral    C   ze dz =                                           1 z
                                                                                 1        
                                                                                       +
                   (a) 3 i              (b) 5 i                        (a) 4 −   ln2 i
                                                                                 2         4
                   (c) 7 i              (d) 9 i                                  1        
                                                                             −
                                                                                         +
                                 →
            64.    Let  : f C  / 3i C  defined by                        (b)  4 +  2 ln2 i   4
                             z i −
                    f  ( ) z =                                                   1        
                            iz +  3                                      (c) 4 +   ln2 i −
                                                                                 2         4

                   Which of the following statements                             1         
                                                                                       +
                   about f is FALSE?                                     (d) 4 −   ln2 i
                                                                                 2         2
                   (a) f is formal on C/3i
                                                                              
                                                                  68.    If a C  with  a    1, then the value
                   (b) f maps circles in C/3i onto circles                        2
                                                                              −
                   in C                                                  of  1 a         dz  dz  where   is
                                                                                       z a   2
                                                                                          +
                   (c) All the fixed points of f in the
                   region z   C  :Im ( )  0z                         the simple closed curve  z =  1 taken
                                                                         with the positive orientation is
                   (d) There is no straight line in C/3i

                   which is mapped onto a straight line           69.    Let  D = z  C  : z    1 . Then there
                   in C by f.                                            exists a non-constant analytic
                                                                         function f on D such that for all
                                            2
                                  f
            65.    The function  ( ) z =  z +   iz + 1 is                n   2
                   differentiable at
                                                                                   − 1  
                   (a) i                 (b) 1                           (a)  f     n      =  0
                                                                                     
                   (c) -i                (d) no point in C
                                                                                   1   

            66.    The radius of convergence of the                      (b)  f       n      =  0
                                  
                   power series    4 ( ) 1 n z−  n  2n   is
                                 n= 0                                              1   
                                                                         (c)  f    1 −       =  0
                                        ( )  0  and let
            67.    Let  =  z  C  :Im z                                         n 
                   C be a smooth curve lying in  with                             1  1   
                                                                         (d)  f    −       =  0
                                                                                 2  n 






                                                            144
   141   142   143   144   145   146   147   148   149   150   151