Thread: show this series diverge
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Old July 3rd, 2009, 05:04 PM
halbard halbard is offline
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Obviously L>0. There is a integer N such that na_n>L/2 for all n\geq N. Thus a_n>L/(2n) for all n\geq N, so \sum a_ndiverges by comparison with \sum L/(2n).
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