Thread: Problem 36
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Old September 6th, 2007, 05:09 PM
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Quote:
What?
A_n = n.a_n
a_n \to 0 because is a convergent series.
and a_{n+1}/a_n<1
then \lim \frac{A_{n+1}}{A_n} = \lim \frac{(n+1)}{n}. \frac{a_{n+1}}{{a_n}} < 1
so A_n \to 0