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Source: 2023 AMC 12A P25

November 9, 2023
AMCAMC 12trigonometry2023 AMC2023 AMC 12ASequences

Problem Statement

There is a unique sequence of integers a1,a2,a2023a_1, a_2, \cdots a_{2023} such that tan2023x=a1tanx+a3tan3x+a5tan5x++a2023tan2023x1+a2tan2x+a4tan4x+a2022tan2022x \tan2023x = \frac{a_1 \tan x + a_3 \tan^3 x + a_5 \tan^5 x + \cdots + a_{2023} \tan^{2023} x}{1 + a_2 \tan^2 x + a_4 \tan^4 x \cdots + a_{2022} \tan^{2022} x} whenever tan2023x\tan 2023x is defined. What is a2023?a_{2023}?
<spanclass=latexbold>(A)</span>2023<spanclass=latexbold>(B)</span>2022<spanclass=latexbold>(C)</span>1<spanclass=latexbold>(D)</span>1<spanclass=latexbold>(E)</span>2023<span class='latex-bold'>(A) </span> -2023 \qquad<span class='latex-bold'>(B) </span> -2022 \qquad<span class='latex-bold'>(C) </span> -1 \qquad<span class='latex-bold'>(D) </span> 1 \qquad<span class='latex-bold'>(E) </span> 2023