Another Infinite Limit - Quite stuck

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Homework Help Overview

The discussion revolves around evaluating the limit of a rational function as \( t \) approaches infinity, specifically the expression \( \lim_{t \to \infty} \frac {5t+2}{t^{2}-6t+1} \). Participants are exploring the behavior of the function and the implications of dividing by increasingly large values.

Discussion Character

  • Exploratory, Mathematical reasoning, Assumption checking

Approaches and Questions Raised

  • The original poster expresses difficulty in determining the first step to take in solving the limit. They mention attempts to factor the denominator and simplify the expression by dividing by \( t \). Other participants suggest similar approaches and discuss the behavior of the numerator and denominator as \( t \) approaches infinity.

Discussion Status

Participants are actively engaging with the problem, with some providing guidance on how to approach the limit. There is a recognition of the relationship between constants and infinity, and the discussion is exploring the implications of these concepts without reaching a definitive conclusion.

Contextual Notes

The original poster notes that the expected answer is 0 according to the textbook, which adds a layer of complexity to their understanding of the limit's behavior.

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Homework Statement



[tex]\lim_{t \to \infty} \frac {5t+2}{t^{2}-6t+1}[/tex]

Homework Equations


The Attempt at a Solution



Like the title says i am quite stuck, I don't see the first move to make, so if someone could point me in the right direction instead of telling me the answer it would be appreciated.

I tried to factor the bottom trinomial but it wouldn't help out anyway, and fatoring out a t from the top and either a t or t^{2} from the bottom doesn't seem to get me any where. And the answer is suppose to be 0, according to the book.

thanks again!
 
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You can start in a similar way to your last problem and factor out a t from both top and bottom. Look then at what the numerator and denominator tend to when t approaches infinity.
 
ok well if you go at it that way it will be:

[tex]\lim_{t \to \infty} \frac {t(5+2t^{-1})}{t(t-6+t^{-1})}[/tex]

[tex]\lim_{t \to \infty} \frac {5+2t^{-1}}{t-6+t^{-1}}[/tex]

which is saying that when:

[tex]H= \infty \;\;\;\;\;and\;\;\;\;\; \epsilon=\frac{1}{H} = infinitesimal[/tex]

it is:

[tex]\frac {5 + \epsilon}{H-6+\epsilon}[/tex]

which is basically 5 divided by infinity, I don't see why that that equals 0

according to my notes an a constant number divided by an infinite number is going to be an infinitesimal number, is that why the limit is 0? because

[tex]\frac {5}{H} = \epsilon[/tex]

and epsilon is going to be infinitely close to 0?
 
The larger H gets, the smaller epsilon gets, so yes, 5/H can be made arbitrarily close to zero.
 
ok thanks for the help again guys
 

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