MHB Limit of Natural Log Sequence: How to Find It Using L'Hopital's Rule?

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To find the limit of the sequence defined by \( a_n = \ln \left(\frac{12n + 2}{-9 + 4n}\right) \), it is suggested to simplify the expression by dividing both the numerator and denominator by \( n \). This results in the form \( a_n = \ln \left(\frac{12 + \frac{2}{n}}{-\frac{9}{n} + 4}\right) \). As \( n \) approaches infinity, the terms \( \frac{2}{n} \) and \( -\frac{9}{n} \) approach zero, leading to the limit \( \ln \left(\frac{12}{4}\right) \). Thus, the limit of the sequence is \( \ln(3) \).
tmt1
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I have this sequence:

$${a}_{n} = \ln \left(\frac{12n + 2}{-9 + 4n}\right)$$

I need to find the limit of this sequence. How can I go about this? Do I need to apply L'Hopitals rule? I'm unsure how to simplify this expression. If I use the rule $\ln(\frac{a}{b}) = \ln a - \ln b$ I get $\infty - \infty$, which I don't think is useful.
 
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tmt said:
I have this sequence:

$${a}_{n} = \ln \left(\frac{12n + 2}{-9 + 4n}\right)$$

I need to find the limit of this sequence. How can I go about this? Do I need to apply L'Hopitals rule? I'm unsure how to simplify this expression. If I use the rule $\ln(\frac{a}{b}) = \ln a - \ln b$ I get $\infty - \infty$, which I don't think is useful.

Hi tmt, :)

Here's a hint. Divide both the numerator and the denominator of the fraction inside the denominator by $n$ so that you get,

$${a}_{n} = \ln \left(\frac{12 + \frac{2}{n}}{-\frac{9}{n} + 4}\right)$$

Try to continue from here. :)
 

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