Solving an indeterminate 0/0 limit without L'Hospital

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SUMMARY

The limit \displaystyle\lim_{x \to{1}}{x^{\frac{1}{x-1}}} is evaluated as an indeterminate form of 1^{\infty}. While L'Hospital's rule is typically used for limits resulting in forms like 0/0, this limit can be approached by taking the natural logarithm, leading to the expression ln(y) = \frac{ln(x)}{x-1}, which does yield a 0/0 form. The discussion highlights that while L'Hospital's rule can be applied indirectly, the participants express difficulty in finding a simpler method to solve the limit without it.

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Hernaner28
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Hi! I'd like to know how to solve the following limit without having to use L'Hospital's rule:

\displaystyle\lim_{x \to{1}}{x^{\frac{1}{x-1}}}

I've already solved it using the derivative rules but I want to know how to solve it without them. Thanks for your help!

EDIT: I was mistaken, it's not a 0/0 indetermiante limit, it's 1^infinity. Edit the title, thanks!
 
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Does the limit from the left equal the limit from the right? Also, l'Hospital's rule doesn't apply to this kind of limit. What kinds does[\I] it apply to?
 
There's one point when you're solving this limit that you get an indeterminate 0/0 limit:

e\displaystyle\lim_{x \to{1}}{\frac{log(x)}{x-1}}

When you get there you may apply L'Hospital's rule but I want to know how to continue without using it.
 
Well, scurty, you can use L'Hopital, indirectly: If y= x^{1/(x-1)} then ln(y)= (ln(x))/(x- 1)which is of the form 0/0. Unfortunately, Hernaner28, I don't see any simple way to do this other than L'Hopital's rule.
 
HallsofIvy said:
Well, scurty, you can use L'Hopital, indirectly: If y= x^{1/(x-1)} then ln(y)= (ln(x))/(x- 1)which is of the form 0/0. Unfortunately, Hernaner28, I don't see any simple way to do this other than L'Hopital's rule.

I'm confused, I thought the limit doesn't exist? The limit from the left doesn't equal the limit from the right.

Edit: I'm on a mobile phone and I completely missed the x being raised to the power, I just saw the power. The x blended in with the lim. Okay, I understand what is being asked now.
 

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