Page 151 - Engineering Mathematics Workbook_Final
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Complex Variables

            105.  The value of ‘P’ such that the                  109.  The value of
                   function                                                 z      cos z       dz  is

                            1                       1    px              1 =  ( z z −  2 )(z −  ) 4
                                    2
                    f  ( ) z =  log ( x +  y 2 ) i+  tan −    
                            2                            y                 i                     i 
                    is analytic is                                       (a)                   (b) −
                                                                              4                      4

                   (a) 1                 (b) -1                          (c)  i               (d) 2 i 

                   (c) 2                 (d) -2                   110.  Let ‘C’ be the circle  z =  1 in the


                                          sin (z −  ) 1                  complex plane described in counter
            106.  The function  ( ) z =               at z                                      1 z
                                                                                                 +
                                  f
                                             z − 1                       clock wise then    c          dz
                                                                                                     )
                                                                                                −
                   = 1 is                                                                    (2 zi z
                                                                                                   −
                                                                                                      i
                   (a) removable singular                                (a)  i               (b)  
                                                                                                   −
                                                                         (c) 2 i              (d)  2 i 
                   (b) essential singular
                                                                                                         
                                                                                                 2
                                                                                              
                   (c) pole of order 2                            111.  The value of     c   sin z + cos z 2  dz
                                                                                            (z −  4 )(z −  ) 2
                   (d) none
                                                                         where  z =  3 is
                                          z −  sin z
            107.  The function  ( ) z =              at z =              (a) 2 i              (b)  2 i 
                                                                                                   −
                                  f
                                             z 3
                                                                                                   −
                                                                                                      i
                   0 is                                                  (c)  i               (d)  
                   (a) removable singular                         112.  The value of     c   sec z dz  where ‘C’ is
                                                                          z = 1 is
                   (b) essential singular
                                                                         (a) 0                 (b) 2 i 
                   (c) pole of order 2
                                                                                                   
                   (d) none                                              (c)  i               (d)
                                                                                                   2
                                                1  
            108.  The function  ( ) sinf z =              at                       c   1
                                                 −
                                               1 z              113.  The value of       z +  4 dz  where ‘c’
                                                                                            2
                   z = 1 is                                              is

                   (a) removable singular                                    i                     
                                                                         (a)                   (b) −
                   (b) essential singular                                     2                      2
                                                                               i                  i
                   (c) zero of the function                              (c) −                 (d)
                                                                               2                   2
                   (d) none




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