relations between the root test and the ratio test
I know the theorem is correct if they are exist
liminfn→∞An+1An≤liminfn→∞(An)1/n≤limsupn→∞(An)1/n≤limsupn→∞An+1An
Here is the 1st question.
If
liminfn→∞An+1An
and
limsupn→∞An+1An
are ∞
then,
liminfn→∞(An)1/n
and
limsupn→∞(An)1/n
are ∞?
And 2nd question is
limn→∞|An+1||An|=∞
then limn→∞(An)1/n=∞
Actually, 2nd question looks like easy, but I can't prove yet.
Could you please help me?
Thanks
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