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 Thread: Infinite 0.9 Not Equal To 1 View Single Post
 06-13-2008 #17 Sillysidley   Join Date: Oct 2006 Posts: 822 Meh hunter, I doubt that most people on here calculus... at least I don't I don't even remember the formula for the sum of a general geometric series, I just derive it when I need to. But for the $a+ar+ar^2+ar^3+...$, the formula's $\frac{a}{1-r}$ when $|r<1|$, the proof works. __________________ .