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2022 AMC 12B Question 11

AMC12 · 2022 AMC 12B

Question 11

Let $$
\begin{aligned} f(n) &= \left(\dfrac{-1 + i\sqrt3}{2}\right)^n \\ &\quad {}+ \left(\dfrac{-1 - i\sqrt3}{2}\right)^n, \end{aligned}
$$ where $i = \sqrt{-1}.$ What is $f(2022)?$
  1. $-2$
  2. $-1$
  3. $0$
  4. $\sqrt3$
  5. $2$