Does Proving An/Bn -> L Ensure An Converges to BnL as n Approaches Infinity?

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The discussion centers on the convergence of sequences An and Bn, given that An/Bn approaches L as n approaches infinity. It is established that both sequences converge to zero and have positive terms. The user seeks to demonstrate that An converges to BnL, leveraging the limit definition and the relationship between the sequences. The conclusion drawn is that since both sequences converge to zero, it is trivial to assert that BnL also converges to zero, thereby confirming that An and BnL converge to the same limit.

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I am given that An/Bn -> L, as n goes to infinity, where An and Bn are sequences. I also know that An and Bn converge to zero and have positive terms.
Pick some E>0, and by definition of the limit there exists an N such |An/Bn - L| < E for all n>N.
Because Bn converges to zero, the sequence is bound by M.

The next step is when my question comes in because I have never really shown that a sequence converges to a sequence.

1/M|An-BnL| < 1/Bn|An-BnL|= |An/Bn - L|< E

Therefore take E to be E/M, and An converges to BnL.

Correct?
 
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It doesn't make sense to say that "a sequence converges to a sequence". What you are showing is that two sequences have the same limit. But if you have already said that \{A_n\} and \{B_n\} converge to 0, It is trivial that \{B_nL\} also converges to 0 and so that \{A_n\} and \{B_nL\} converge to the same limit- 0.
 
I should probably let you know my aim is to show that Bn+1/Bn <1 if I know that An+1/An <1. Would my method allow me to replace An+1 by Bn+1L and An by BnL in limit as n goes to infinity?
 

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