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2019 AMC 12A Question 14

AMC12 · 2019 AMC 12A

Question 14

For a certain complex number $c,$ the polynomial

$$
\begin{aligned} P(x) &= (x^2 - 2x + 2) \\ &\quad {}\cdot (x^2 - cx + 4) \\ &\quad {}\cdot (x^2 - 4x + 8) \end{aligned}
$$

has exactly $4$ distinct roots. What is $|c|?$
  1. $2$
  2. $\sqrt{6}$
  3. $2\sqrt{2}$
  4. $3$
  5. $\sqrt{10}$