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If  ω is the cube root of unity, then what is the value of

  1. 1
  3. 0
  5. -1

Answer (Detailed Solution Below)

Option 3 : 0

Detailed Solution

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Concept:

If the 1, ω and ω2  are the cube roots of unity, then 1 + ω + ω2 = 0

If any row and column have all the elements as zero in the square matrix, then the determinant is zero.

Calculation:

D = 

R3 = R3 + R1 + R2

D = 

D =  = 0

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