Question
Suppose that $s_1>s_2>0$ and let $s_{n+1}=\frac{1}{2}\left(s_n+s_{n-1}\right)$ for $n \geq 2$. Show that $\left(s_n\right)$ converges. [Hint: Show that $\left(s_{2 n-1}\right)$ decreases and $\left(s_{2 n}\right)$ increases.]
Step 1
We have the original sequence defined by \( s_{n+1} = \frac{1}{2}(s_n + s_{n-1}) \). We will analyze the subsequences \( s_{2n-1} \) (odd-indexed terms) and \( s_{2n} \) (even-indexed terms). Show more…
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