deletions | additions       diff --git a/ratio.tex b/ratio.tex  index bc3424e..a9d4980 100644  --- a/ratio.tex  +++ b/ratio.tex 
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If I use the Ratio Test to determine whether S converges, I need to   determine:  lim |a(n + 1) ÷ a(n)|  n→∞ \begin{align}  \lim_{n\to\infty}\left|\:a(n\:+\:1)\hspace{1em}\div\hspace{1em}a(n)\:\right|  \end{align}  Apply Ratio Test:  \begin{align}  \lim_{n\to\infty}\left|\:a(n\:+\:1)\hspace{1em}\div\hspace{1em}a(n)\:\right| \\[1em]  \lim_{n\to\infty}\left|\:\frac{9^{(n\:+\:1)}}{(n\:+\:1\:+\:1)\cdot 2^{(2(n\:+\:1)\:-\:1)}}\hspace{1em}\div\hspace{1em}\frac{9^n}{(n\:+\:1)\cdot 2^{(2n\:-\:1)}}\:\right| \\[1em]  \end{align}  \end{document}