Write the complex number in the polar form.
Let   z = i -1 = -1 + i = r()                                     ....(i)
        r cos  = - 1                                                                 ...(ii)
       r sin  =  1                                  ...(iii)
Squaring and adding (ii) and (iii) we get
                         r2  = 2                   r =
∴ From (ii) and (iii).
                 Â
                                Â
               Â
Â
∴ Â
Â
  Â
 Â
     Â
Â
Â
 Which is the reequired polar form.
A complex number z is said to be unimodular, if |z|= 1. suppose z1 and z2 are complex numbers such that  is unimodular and z2 is not unimodular. Then, the point z1 lies on a
straight line parallel to X -axis
straight line parallel to Y -axis
circle of radius 2
circle of radius 2