#Real Analysis: Proving this series is divergent

9 messages · Page 1 of 1 (latest)

hoary cosmos
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I've tried proving the contrapositive and using the definition of convergence/divergence to no avail. I've tried the limit comparison test as well. Is there any other way I could approach this problem?

candid gyroBOT
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sage mortar
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Hmmm well the way I’d do it is study all the possible cases:
Case1: the sequence an diverges than the series an/(1+an) diverges because it doesn’t have a null limit
Case 2: an converges to a non 0 limit , so an/1+an also converges to an non 0 limit thus the series diverges

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Case 3: an converges to 0 than an/(an/(1+an)=1+an

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Knowing an converges to 0 we have an~(an((1+an)) but the series an diverges thus the series an/(1+an) diverges as well

sage mortar
hoary cosmos
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I actually managed to prove it now but using a different method. Thanks for replying!

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