Trivial limit ( 1 - (-x)^n ) / 1 + x

  • Thread starter davitz
  • Start date
  • Tags
    Limit
In summary, the limit of (1-(-x)^n)/(1+x) as n approaches infinity equals to 1/(1+x) for any power of n. This is because, for x values between -1 and 1, as n approaches infinity, x^n will tend to 0 and therefore the entire expression will simplify to 1/(1+x). This can be seen by applying the limit (1+1/n)^n, which approaches e, but only works for x values between 0 and 1.
  • #1
davitz
2
0

Homework Statement



lim ( 1 - ( - x ) ^ n ) / ( 1 + x ) as n -> infinity

Homework Equations



I can't understand why this equals to 1 / ( 1 + x ) (No matter what power of " n " was x e.q: x ^ 2n or x ^ ( n ^ 2 )

The Attempt at a Solution



I have no clue what rule to apply. I thought it might be a case of using the lim ( 1 + 1 / n ) ^ n to get to " e " but this seems like a non-sense in this case.
 

Attachments

  • equation.png
    equation.png
    738 bytes · Views: 468
Physics news on Phys.org
  • #2
I think you first need to have a condition on x before that is true.

0 < x < 1, right?

If so, anything between 0 and 1 raised to a power of infinity will tend to 0, as it gets smaller with each successive multiplication.

[tex]\lim_{n\to \infty} x^n = 0[/tex]

where -1<x<1
 
  • #3
Thank so much for the reply! Yes, x > -1 and x < 1 or -1 < x < 1 and now I understand why this is the result!

Thank you again!
 
  • #4
Glad to have been of help! :smile:
 

1. What is a trivial limit?

A trivial limit is a mathematical concept that describes what happens to a function as the input approaches a certain value, typically infinity or negative infinity. In the case of the function (1 - (-x)^n) / (1 + x), the trivial limit would be the value of the function as x approaches infinity.

2. How is the trivial limit calculated?

The trivial limit can be calculated using various methods, such as algebraic manipulation, L'Hopital's rule, or using a graphing calculator. In the case of (1 - (-x)^n) / (1 + x), the limit can be found by simplifying the function and then evaluating it as x approaches infinity.

3. What is the significance of the trivial limit?

The trivial limit helps us understand the behavior of a function as the input approaches a certain value. It can also help us determine the end behavior of a function and identify any horizontal asymptotes.

4. What is the limit as x approaches infinity?

The limit as x approaches infinity for (1 - (-x)^n) / (1 + x) depends on the value of n. If n is even, the limit will approach 1 as x approaches infinity. If n is odd, the limit will approach -1 as x approaches infinity.

5. Can the trivial limit be used to determine the convergence of a series?

Yes, the trivial limit can be used to determine the convergence of a series. If the trivial limit is equal to a finite number, the series is said to converge. If the trivial limit is equal to infinity or negative infinity, the series is said to diverge.

Similar threads

  • Calculus and Beyond Homework Help
Replies
1
Views
251
  • Calculus and Beyond Homework Help
Replies
8
Views
659
  • Calculus and Beyond Homework Help
Replies
17
Views
605
  • Calculus and Beyond Homework Help
Replies
2
Views
708
  • Calculus and Beyond Homework Help
Replies
4
Views
301
  • Calculus and Beyond Homework Help
Replies
6
Views
940
  • Calculus and Beyond Homework Help
Replies
3
Views
1K
Replies
23
Views
1K
  • Calculus and Beyond Homework Help
Replies
6
Views
884
  • Calculus and Beyond Homework Help
Replies
2
Views
840
Back
Top