Limit ln(n-1/n+1) as n->infinity

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Homework Statement


Hi! I need help confirming the limit of ln(n-1/n+1) as n->infinity.

If you multiply top and bottom of the quotient by 1/n you'd end up with ln(1) = 0, no? I must be missing something rather simple here because my hp50 won't even compute. Thanks!

Homework Statement

 
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AFinch said:

Homework Statement


Hi! I need help confirming the limit of ln(n-1/n+1) as n->infinity.

If you multiply top and bottom of the quotient by 1/n you'd end up with ln(1) = 0, no? I must be missing something rather simple here because my hp50 won't even compute. Thanks!

Homework Statement


Yes, you did it correctly. I'm not sure why the hp50 has problems.
 
Last edited:
Thank you! After getting your response I looked further into the problem with the hp and figured it out. I had a 1. instead of 1 (sans decimal), and it won't take a limit with the decimal because it's a "real" number. This was of much help.
 
AFinch said:

Homework Statement


Hi! I need help confirming the limit of ln(n-1/n+1) as n->infinity.

If you multiply top and bottom of the quotient by 1/n you'd end up with ln(1) = 0, no? I must be missing something rather simple here because my hp50 won't even compute. Thanks!

Homework Statement


You should realize that what you have written is ln[n + 1 - 1/n], which has no limit. Did you really mean ln[(n-1)/(n+1)]? If so, use brackets!

RGV
 
Yes ln[(x-1)/(x+1)] is what I actually meant, thanks for correcting my mistake.
 
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