Solving Limit Without L'Hospital's Rule

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Homework Help Overview

The discussion revolves around evaluating a limit as x approaches 2 for the expression involving a polynomial in both the numerator and denominator. The original poster expresses uncertainty about methods other than L'Hospital's rule to solve the limit problem.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants discuss the presence of a common factor in the numerator and denominator that leads to an indeterminate form. There are mentions of factoring and polynomial division as alternative methods to resolve the limit.

Discussion Status

The conversation is ongoing, with some participants suggesting methods like canceling common factors and using polynomial division. The original poster acknowledges the need for these alternative approaches but has not yet fully explored them.

Contextual Notes

The original poster has already applied L'Hospital's rule and is seeking a different method, indicating a desire to adhere to homework guidelines that may discourage its use.

chislam
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I was working out a limit problem and even though I solved it using L'hospital's rule, I do not know how to solve it another way which was probably the intended way. Here's the limit:

[tex]\lim_{x\rightarrow2} \frac{x^4 - x^3 + x^2 - 4x - 4}{2x^2 - 5x + 2}[/tex]

So I used L'hospital's rule and got 20/3 but I want to know another method.

Thanks
 
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The numerator and denominator have a common factor of (x-2) that is causing it to have a 0/0 form. If you cancel out that common factor, you can just put x=2.
 
Yeah I figured that was the case, but I wasn't able to factor it out in the numerator.
 
Just do polynomial division of (x-2) into the numerator. You know you'll get zero remainder, right?
 
Doh! Lol, I completely forgot about synthetic division.
 

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