Seq Convergence: Does a_n = (-1)^(n+1)/(2n-1) Converge or Diverge?

In summary, the conversation discusses whether the given sequence is convergent or divergent, with the equation \displaystyle a_{n} = \frac{(-1)^{n+1}}{2n-1}. The discussion also mentions the possibility of using the squeeze theorem and taking the natural logarithm of the numerator and denominator. The conversation then shifts to discussing the homework template and clarifying if the question is about a sequence or a series.
  • #1
whatlifeforme
219
0

Homework Statement


Converge or diverge?

Homework Equations


[itex]\displaystyle a_{n} = \frac{(-1)^{n+1}}{2n-1}[/itex]

The Attempt at a Solution


all i know is to perhaps take ln of numerator and denominator to get the exponent down below?
 
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  • #2
whatlifeforme said:

Homework Statement


Converge or diverge?

Homework Equations


[itex]\displaystyle a_{n} = \frac{(-1)^{n+1}}{2n-1}[/itex]

The Attempt at a Solution


all i know is to perhaps take ln of numerator and denominator to get the exponent down below?
Do you know the squeeze theorem ?
 
  • #3
SammyS said:
Do you know the squeeze theorem ?

I do.
 
  • #4
whatlifeforme said:
I do.

It appears the sequence is conditionally convergent.

1. What is ##\sum |a_n| = \space ?##

2. Is ##a_n > a_{n+1}##? For sufficiently large n.

3. lim n→∞ ... = ...
 
  • #5
whatlifeforme said:

Homework Statement


Converge or diverge?

Homework Equations


[itex]\displaystyle a_{n} = \frac{(-1)^{n+1}}{2n-1}[/itex]

The Attempt at a Solution


all i know is to perhaps take ln of numerator and denominator to get the exponent down below?

Are you asking about a sequence or a series? You should fill in part one of the homework template more completely.
 
Last edited:
  • #6
sequence.
 
  • #7
So show us what you have done so far in thinking about whether that sequence has a limit.
 

FAQ: Seq Convergence: Does a_n = (-1)^(n+1)/(2n-1) Converge or Diverge?

What is Seq Convergence?

Seq Convergence refers to the behavior of a sequence, which is a list of numbers that follow a specific pattern. In simple terms, it is the tendency of a sequence to approach a specific value as the number of terms increases.

What is the formula for a_n in the sequence (-1)^(n+1)/(2n-1)?

The formula for a_n in this sequence is (-1) raised to the power of n+1, divided by 2n-1. This means that the first term (n=1) is equal to -1/1, the second term (n=2) is equal to 1/3, the third term (n=3) is equal to -1/5, and so on.

How do you determine if a sequence converges or diverges?

To determine if a sequence converges or diverges, you can use the limit test. If the limit of the sequence approaches a specific value as n approaches infinity, then the sequence converges. If the limit does not exist or approaches infinity, then the sequence diverges.

What is the limit of the sequence (-1)^(n+1)/(2n-1)?

The limit of this sequence is 0, as n approaches infinity. This means that the sequence converges to 0.

Is the sequence (-1)^(n+1)/(2n-1) convergent or divergent?

The sequence (-1)^(n+1)/(2n-1) is convergent, as the limit of the sequence approaches 0 as n approaches infinity. This can also be confirmed by graphing the sequence, which will show that the terms get closer and closer to 0 as n increases.

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