Limit WITHOUT using l'hospital

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Homework Help Overview

The discussion revolves around evaluating the limit of a quotient involving polynomial expressions as \( x \) approaches 1, specifically \(\lim_{x\to1} \frac{x^{p}-1}{x^{q}-1}\), where \( p \) and \( q \) are natural numbers. Participants are exploring methods to find this limit without employing L'Hôpital's rule.

Discussion Character

  • Exploratory, Mathematical reasoning, Assumption checking

Approaches and Questions Raised

  • Participants discuss rewriting the limit expression and consider using binomial expansion. Others suggest factoring the expressions to simplify the limit evaluation.

Discussion Status

The conversation is active, with participants sharing different approaches and methods. Some have expressed realization that their initial methods were overly complicated, indicating a productive exploration of simpler techniques.

Contextual Notes

There is an emphasis on avoiding L'Hôpital's rule, which may influence the methods discussed. The participants are working within the constraints of natural numbers for \( p \) and \( q \).

Doom of Doom
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For [tex]p,q\in \mathbb{N}[/tex], determine [tex]\lim_{x\to1} \frac{x^{p}-1}{x^{q}-1}[/tex]

I know that it should be p/q. Without using L'hospitals rule, how do I determine it?
 
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The quotient can be rewritten as (1-xp )/(1-xq ). Since x is less than 1 try a binomial expansion.
 
Factoring :)
 
NoMoreExams said:
Factoring :)

Got it! My methods of trying were way more complicated. Don't know why I didn't think of that at first!

(x^n) - 1=(x-1)(x^(n-1) + ... + x + 1)

Thanks NoMoreExams
 

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