Prove that the lim of the sequence (S_n)=0

  • Thread starter bingo92
  • Start date
  • Tags
    Sequence
For all n, yes?And what can you tell me about the limit of -tn and tn?In summary, the conversation discusses proving that the limit of a sequence (s_n) is equal to 0, given that the limit of another sequence (t_n) is also equal to 0 and that the absolute value of (s_n) is always less than or equal to (t_n). The expert suggests using the squeeze theorem to show that the limit of (s_n) is indeed equal to 0.
  • #1
bingo92
7
0

Homework Statement


suppose that (s_n) and (t_n) are sequences in which abs(s_n)≤t_n for all n and let lim(t_n)=0. Prove that lim (s_n)=0.

The Attempt at a Solution


I find absolute values to be really sketchy to work with I'm really in the dark if this is at all correct:

Let ε>0 be given, then -ε<(t_n)<ε for some n>N since the limit exists. Since -t_n≤ s_n ≤ t_n for all we can say that for -ε<-t_n≤ S_n≤t_n<ε for n>N above. hence lim(S_n)=0.

If you have any suggestion about how to deal with the absolutes in a general manner in these kind of proofs I'd be happy to hear it.

Homework Statement


Homework Equations


The Attempt at a Solution

 
Physics news on Phys.org
  • #2
Ahh now there's a very nice trick you can apply here. Recall the squeeze theorem works the same way it does for functions as it does for sequences.

So :

|sn| ≤ tn

Tells us that :

-tn ≤ sn ≤ tn
 

FAQ: Prove that the lim of the sequence (S_n)=0

1. How is the limit of a sequence defined?

The limit of a sequence is defined as the value that the sequence approaches as the number of terms in the sequence approaches infinity.

2. Why is it important to prove that the limit of a sequence is 0?

Proving that the limit of a sequence is 0 indicates that the terms of the sequence are getting closer and closer to 0 as the number of terms increases. This can help us understand the overall behavior of the sequence and make predictions about its future values.

3. What does it mean if the limit of a sequence is 0?

If the limit of a sequence is 0, it means that the terms of the sequence are getting closer and closer to 0 as the number of terms increases. This can also be interpreted as the sequence approaching 0 as its infinite term.

4. How is the limit of a sequence (S_n)=0 proved?

The limit of a sequence (S_n)=0 is proved by showing that for any given small positive number, there exists a point in the sequence after which all the terms are within that small positive number of 0.

5. Can the limit of a sequence (S_n)=0 be negative?

No, the limit of a sequence (S_n)=0 can only be 0 or a positive value. This is because when we say the limit of a sequence is 0, it means that the terms of the sequence are getting closer and closer to 0 as the number of terms increases. If the limit were to be a negative value, the terms would be getting closer and closer to that negative value, which is not possible when we say the limit is 0.

Back
Top