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2004 AMC 12A Question 23

AMC12 · 2004 AMC 12A

Question 23

A polynomial $$
\begin{aligned} &P(x) = c_{2004} x^{2004} + c_{2003} x^{2003} \\ &\quad {}+ \cdots + c_1 x + c_0 \end{aligned}
$$ has real coefficients with $c_{2004} \ne 0$ and $2004$ distinct complex zeros $z_k = a_k + b_k i,$ $1 \le k \le 2004$ with $a_k$ and $b_k$ real, $a_1 = b_1 = 0,$ and $$
\sum_{k=1}^{2004} a_k = \sum_{k=1}^{2004} b_k.
$$ Which of the following quantities can be a nonzero number?
  1. $c_0$
  2. $c_{2003}$
  3. $b_2 b_3 \ldots b_{2004}$
  4. $\displaystyle\sum_{k=1}^{2004} a_k$
  5. $\displaystyle\sum_{k=1}^{2004} c_k$