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If w is complex cube root of unity, then w-16 =
a)w        
b)1                         
c)w2       
d)w
-1

c



If w is complex cube root of unity, then w-27 =
a)w        
b) 1                        
c)w2       
d)
w

b



Cube roots of 8 are:
a) 2,2w,2w2                                 
b) -2,-2w,-2w2
c) 2,-2w,-2w2                         
d) 2,-2w,2w2

a

Cube roots of -27 are:
a) -3,-3w,-3w2                           
b) -2,-2w,-2w2
c) 3,-2w,-3w2                         
d) 2,-2w,2w2

a

Cube roots of 64 are:
a) -4,-4w,-4w2                           
b) -2,-4w,-2w2
c) 4,4w,4w2                           
d) 2,-2w,2w2

c

(1-w-w2)5=…………
a) 16       
b) 64                       
c) 6         
d)32

d

Solution:(1-w-w2)5
(1-(w+w2))5                            As, 1+w+w2=0
Or w+w2=-1                           = (1-(-1))5
(1+1)5     = (2)5                                  =32