The least positive integer n for which 1 3 1– 3 n i i æ ö + ç ÷ è ø = 1, is

Question:
The least positive integer $\mathrm{n}$ for which $\left(\frac{1+i \sqrt{3}}{1-i \sqrt{3}}\right)^{n}=1$, is

Correct Option: 4

JEE Main Previous Year 1 Question of JEE Main from Mathematics Complex Numbers and Quadratic Equations chapter.