MHT CET202618 April 2026Morning ShiftMathematicsComplex NumberActual
The value of ( -1+i 3 2 )¹⁸ + ( -1-i 3 2 )¹⁸ is
Options
- A2
- B35
- C3
- D3 2
Correct answer
A. 2
Step-by-step solution
Let = -1+i 3 2 and ^2 = -1-i 3 2 be the complex cube roots of unity. The given expression can be written as ¹⁸ + ( ^2)¹⁸ . Since ^3 = 1 , we have ¹⁸ = ( ^3)^6 = 1^6 = 1 . Similarly, ( ^2)¹⁸ = ³⁶ = ( ^3)¹² = 1¹² = 1 . Therefore, the value of the expression is 1 + 1 = 2 . Answer: 2