Limits of Function f(x) with Greatest Integer [x]: Problem Analysis

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Homework Help Overview

The discussion revolves around evaluating the limit of a function involving the greatest integer function as x approaches 1 from the right. The function is defined as f(x) = lim n->infinity [x]^n / (x^n +1), where [x] denotes the greatest integer less than or equal to x. Participants are exploring the behavior of this limit and comparing it to another limit involving the same function.

Discussion Character

  • Exploratory, Assumption checking, Conceptual clarification

Approaches and Questions Raised

  • The original poster expresses confusion about the two limits and questions their understanding of the behavior of the function as n approaches infinity and x approaches 1. Other participants clarify the definition of the greatest integer function and discuss the limits involved, with some suggesting that the limit should be 1.

Discussion Status

The discussion is ongoing, with participants providing insights and clarifications regarding the limits. Some guidance has been offered about evaluating the limits, but there is no explicit consensus on the final value of the limit or the correct approach to take.

Contextual Notes

Participants are working under the assumption that x is approaching 1 from above and are considering the implications of the greatest integer function in this context. There is a mention of evaluating limits for values of x between 1 and 2.

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Given a function f(x) = lim n->infintiy [x]^n / (x^n +1) , where [x] is a greatest integer function.
What is the limit value of lim x->1+ f(x) ?
Is the limit found above the same with lim n->infinity (lim x->1+ [x]^n / (x^n +1) ) ?
I am rather confused with the above two cases. I don't know how to think of it. I have such kind of thought: if n tends to infinity first, even x becomes very close to 1, the value is still at infinity. If x tends to 1 faster, even n tends to infinity, the value is still 1.
What's wrong with my concepts?
 
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So [x] means the greatest integer less than or equal to x? If so, what is the limit x->1+ of [x]/(1+x^n)?
 
Yes, but I m not sure about the limit..I think it should be 1..
 
Note that both numerator and denominator exist and are nonzero for all x>1, and thus the limit is rather easy to evaluate.
 
as x increases without bound, the greatest integer returns decimal values of n.something back to n, as the denominator keeps growing; approaching infinity.
 
In fact, since you want to take the limit as x goes to 1 from above, you only need to look at values of x between 1 and 2.

[itex]1^n[/itex] is pretty easy, isn't it?
 
For that matter, try just plugging 1 into the equation.
 

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