Real Analysis: proving a sequence converges and finding its limit.

TeenieBopper
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Homework Statement


Suppose r>1. Prove the sequence [itex]\sqrt[n]{1 + r^{n}}[/itex] converges and find its limit.


Homework Equations





The Attempt at a Solution



It's obvious that the sequence converges to r, so I know where I need to end up. My first instinct is to use the squeeze theorem. It's obvious that [itex]\sqrt[n]{r^{n}}[/itex]<[itex]\sqrt[n]{1 + r^{n}}[/itex]. However, I'm having difficulty finding a sequence that's greater than [itex]\sqrt[n]{1 + r^{n}}[/itex] but also converges to r.
 
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TeenieBopper said:

Homework Statement


Suppose r>1. Prove the sequence [itex]\sqrt[n]{1 + r^{n}}[/itex] converges and find its limit.


Homework Equations





The Attempt at a Solution



It's obvious that the sequence converges to r, so I know where I need to end up. My first instinct is to use the squeeze theorem. It's obvious that [itex]\sqrt[n]{r^{n}}[/itex]<[itex]\sqrt[n]{1 + r^{n}}[/itex]. However, I'm having difficulty finding a sequence that's greater than [itex]\sqrt[n]{1 + r^{n}}[/itex] but also converges to r.
Try comparing to [itex]\displaystyle \sqrt[n]{2\,r^n}\ .[/itex]
 

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