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August 20th, 2009, 12:11 PM   #1
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limit to infinity of ln n / ln (n+1)

I'm trying to figure out how to find the limit of ln n / ln(n+1) as n approaches infinity. The answer booklet says it's 1. How do I approach this?
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August 20th, 2009, 12:32 PM   #2
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Are you allowed to use l"Hospital's Rule?
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August 20th, 2009, 12:55 PM   #3
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Re: limit to infinity of ln n / ln (n+1)

Use
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August 20th, 2009, 07:12 PM   #4
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Re: limit to infinity of ln n / ln (n+1)

Thanks for the replies. Yes I looked at the rule I can use it. I just have another question what is the derivative of f(x) = ln (x+1)? Do I let u = x + 1, then multiply the derivative of f(x) with the derivative of u?
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August 20th, 2009, 11:19 PM   #5
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You multiply the derivative of f(u) with respect to u by the derivative of u with respect to x and then replace u with x + 1.
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August 21st, 2009, 06:59 AM   #6
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Re: limit to infinity of ln n / ln (n+1)

Once I use the rule I'll end up with (x + 1) / x. Do I just divide each literal by x?
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August 21st, 2009, 11:17 AM   #7
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Yes.
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