2. Questions Bank
  3. JEE Main & Advanced
  4. Mathematics
  5. Complex Numbers and Quadratic Equations

JEE Main & Advanced Mathematics Complex Numbers and Quadratic Equations Question Bank De Moivre's theorem and Roots of unity

  • question_answer
    One of the cube roots of unity is [MP PET 1994, 2003]

    A) \[\frac{-1+i\sqrt{3}}{2}\]

    B) \[\frac{1+i\sqrt{3}}{2}\]

    C) \[\frac{1-i\sqrt{3}}{2}\]

    D) \[\frac{\sqrt{3}-i}{2}\]

    Correct Answer: A

    Solution :

    It is obvious because the cube roots of unity are \[1,\frac{-1+i\sqrt{3}}{2},\frac{-1-i\sqrt{3}}{2}\]


You need to login to perform this action.
You will be redirected in 3 sec spinner