Plot of four fourth roots of (1-2i), then their cubes. 

 

> with(plots):with(plottools):                                                                          # Load graphing libraries
 

> C:=circle([0,0],5^(1/8),color=blue):                                                                  # Enter circle of R = eigth root of 5.
 

> P:=line([0,0],[1,-2],color=red):                                                                      # Enter the point 1-2i.    
 

> R1:=line([0,0],[5^(1/8)*cos(-arctan(2)/4),5^(1/8)*sin(-arctan(2)/4)],color=purple);                   # Enter first root we found.
 

CURVES([[0., 0.], [1.176301073, -.3341624843]], COLOUR(RGB, .47058824, 0., .44705882)) (1)
 

> R2:=line([0,0],[5^(1/8)*cos(-arctan(2)/4+Pi/2),5^(1/8)*sin(-arctan(2)/4+Pi/2)],color=purple);         # Enter second root we found.
 

CURVES([[0., 0.], [.3341624843, 1.176301073]], COLOUR(RGB, .47058824, 0., .44705882)) (2)
 

> R3:=line([0,0],[5^(1/8)*cos(-arctan(2)/4+Pi),5^(1/8)*sin(-arctan(2)/4+Pi)],color=purple);             # Enter third root we found.
 

CURVES([[0., 0.], [-1.176301073, .3341624843]], COLOUR(RGB, .47058824, 0., .44705882)) (3)
 

> R4:=line([0,0],[5^(1/8)*cos(-arctan(2)/4+3*Pi/2),5^(1/8)*sin(-arctan(2)/4+3*Pi/2)],color=purple);     # Enter fourth toor we found.
 

CURVES([[0., 0.], [-.3341624843, -1.176301073]], COLOUR(RGB, .47058824, 0., .44705882)) (4)
 

> display(C,P,R1,R2,R3,R4,view=[-2..2,-2..2]);                                                           # Plot all this!  
 

Plot_2d
 

Next we cube them. 

> R13:=line([0,0],[5^(3/8)*cos(-3*arctan(2)/4),5^(3/8)*sin(-3*arctan(2)/4)],color=purple);
 

CURVES([[0., 0.], [1.233575782, -1.349811956]], COLOUR(RGB, .47058824, 0., .44705882)) (5)
 

> R23:=line([0,0],[5^(3/8)*cos(-3*arctan(2)/4+3*Pi/2),5^(3/8)*sin(-3*arctan(2)/4+3*Pi/2)],color=purple);
 

CURVES([[0., 0.], [-1.349811956, -1.233575782]], COLOUR(RGB, .47058824, 0., .44705882)) (6)
 

> R33:=line([0,0],[5^(3/8)*cos(-3*arctan(2)/4+3*Pi),5^(3/8)*sin(-3*arctan(2)/4+3*Pi)],color=purple);
 

CURVES([[0., 0.], [-1.233575782, 1.349811956]], COLOUR(RGB, .47058824, 0., .44705882)) (7)
 

> R43:=line([0,0],[5^(3/8)*cos(-3*arctan(2)/4+3*3*Pi/2),5^(3/8)*sin(-3*arctan(2)/4+3*3*Pi/2)],color=purple);
 

CURVES([[0., 0.], [1.349811956, 1.233575782]], COLOUR(RGB, .47058824, 0., .44705882)) (8)
 

> display(P,R13,R23,R33,R43,view=[-2..2,-2..2]);
 

Plot_2d
 

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