2025 USA-NA-AIO Round 1, Problem 1, Part 8

Part 8 (10 points, non-coding task)

Compute

\lim_{n \rightarrow \infty} \ \frac{F_n}{F_{n-1}} .
  • Reasoning is required.

  • Your answer shall be written in terms of one or two eigenvalues.

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We notice that | \lambda_0 | > 1 and | \lambda_1 | < 1.

Hence,

\begin{align*} \lim_{n \rightarrow \infty} \ \frac{F_n}{F_{n-1}} & = \boxed{\lambda_0 } . \end{align*}

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