Without using L'Hopital's rule, how can I calaculate this limit?

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Homework Help Overview

The discussion revolves around calculating the limit of the function (x^n - a^n) / (x - a) as x approaches a, without using L'Hopital's rule. The subject area is calculus, specifically limits and indeterminate forms.

Discussion Character

  • Exploratory, Assumption checking, Mathematical reasoning

Approaches and Questions Raised

  • Participants discuss the challenge of resolving indeterminate forms in the limit calculation. Some suggest factoring the expression, while others question whether n is a positive integer, which influences the approach to the problem.

Discussion Status

There is ongoing exploration of different methods to approach the limit. Some participants have offered suggestions for factoring, while others have noted the implications of n's value on the problem. The discussion reflects a mix of attempts and clarifications without a definitive consensus.

Contextual Notes

One participant acknowledges not having followed the forum's posting rules regarding original attempts, which may affect the clarity of the discussion.

Calabi_Yau
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Without using L'Hopital's rule how can I calculate the limit of this function: (xn-an)/(x-a) when x→a

I cannot get rid of the indeterminations no matter what. I would like if you could help me out on this.
 
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Calabi_Yau said:
Without using L'Hopital's rule how can I calculate the limit of this function: (xn-an)/(x-a) when x→a

I cannot get rid of the indeterminations no matter what. I would like if you could help me out on this.

Factor x^n-a^n. For example x^2-a^2=(x-a)(x+a). x^3-a^3=(x-a)(x^2+xa+a^2) etc.
 
Calabi_Yau said:
Without using L'Hopital's rule how can I calculate the limit of this function: (xn-an)/(x-a) when x→a

I cannot get rid of the indeterminations no matter what. I would like if you could help me out on this.

Is n a positive integer? If so, just factor, as Dick has already suggested. If n is not a positive integer, you more-or-less need to use l'Hosptial's rule, whether you want to or not.
 
I figured that out. Took me a while to notice if I factorized x^n-a^n beginning with (x-a)(...) the sum of the other factors would add up to n.a^n-1.

PS: I apologize not having posted my original atempt in solving the problem like the rules require.
 

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