What is the limit of (x/x+1)^x as x tends to infinity?

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Discussion Overview

The discussion centers on finding the limit of the expression (x/x+1)^x as x approaches infinity. Participants explore different interpretations of the expression and various approaches to solving the limit, including mathematical manipulations and transformations.

Discussion Character

  • Mathematical reasoning
  • Debate/contested

Main Points Raised

  • One participant requests assistance in finding the limit of (x/x+1)^x as x tends to infinity.
  • Another participant suggests that the limit is infinity unless the expression is interpreted as \lim_{x \rightarrow \infty} \left ( \frac{x}{x + 1}\right )^x, and emphasizes the importance of proper notation.
  • A subsequent reply reiterates the limit interpretation and introduces the reciprocal limit \lim_{x \rightarrow \infty} \left ( \frac{x+1}{x}\right )^x, asking if the original poster can solve that limit.
  • One participant claims to have solved the limit, presenting a step-by-step transformation leading to the conclusion that as x tends to infinity, the function approaches e^-1.
  • Another participant provides a detailed limit transformation that also concludes with e^-1, indicating a similar approach to the previous claim.

Areas of Agreement / Disagreement

There is no consensus on the limit, as participants present differing interpretations and conclusions. Some participants suggest the limit approaches e^-1, while others initially propose it approaches infinity.

Contextual Notes

Participants express uncertainty regarding the correct interpretation of the expression, highlighting the importance of notation in mathematical limits. There are unresolved steps in the transformations presented.

Who May Find This Useful

Readers interested in mathematical limits, particularly those studying calculus or related fields, may find this discussion relevant.

l33t_V
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Can someone help me with finding the limit of (x/x+1)^x as x tends to infinity
 
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The limit is infinity, unless of course this is what you meant:
[tex]\lim_{x \rightarrow \infty} \left ( \frac{x}{x + 1}\right )^x[/tex]

If you want to write the quotient of x and x + 1, put parentheses around what goes in the denominator, like so: x/(x + 1).
 
unless of course this is what you meant:
[tex]\lim_{x \rightarrow \infty} \left ( \frac{x}{x + 1}\right )^x[/tex]

The reciprocal is
[tex]\lim_{x \rightarrow \infty} \left ( \frac{x+1}{x}\right )^x[/tex]
Can you do that limit?
 
Mark44 said:
The limit is infinity, unless of course this is what you meant:
[tex]\lim_{x \rightarrow \infty} \left ( \frac{x}{x + 1}\right )^x[/tex]

If you want to write the quotient of x and x + 1, put parentheses around what goes in the denominator, like so: x/(x + 1).
Yes, i meant (x/(x+1))^x
 
Last edited:
Never mind, I solved it.

(x/(x(1+1/x)))^x = (1/(1+1/x))^x = 1^x/(1+1/x)^x where 1^x = 1 and (1+(1/x))^x as x tends to inf = e^1

therefore as x tends to infinity the function tends to e^-1
 
[tex]\lim_{x\rightarrow \infty} (x/x+1)^x= \lim _{x\rightarrow \infty} (1+\frac{-1}{x+1})^{-(x+1)\frac{x}{-(x+1)}})=\lim_{x\rightarrow \infty} e^\frac{x}{-(x+1)}}=e^{-1}[/tex]
 

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