Prove √a(n) Converges to 0 | Stuck on Proof

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In summary, the conversation discusses a proof where the given conditions state that a sequence converges to 0. The proof uses the definition of convergence and the concept of epsilon to show that for all n greater than or equal to a certain value, the square root of the sequence term is less than a given value. The conversation also includes a question asking to prove that the square root of the sequence term is eventually less than a specific value, such as 1/100 or 1/1000000.
  • #1
CoachBryan
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I've been messing with this proof for while and I'm stuck on this. I've started with a(n) converges to 0, let epsilon > 0, then there exists an n0 in N such that for all n >= n0.

I'm stuck here thus far. Any help? Thanks for your time.
 
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  • #2
CoachBryan said:
I've been messing with this proof for while and I'm stuck on this. I've started with a(n) converges to 0, let epsilon > 0, then there exists an n0 in N such that for all n >= n0.

I'm stuck here thus far. Any help? Thanks for your time.
The rest of your thought is
For all n >= n0, ##\sqrt{a_n} < \epsilon##.

What are the given conditions? Is it an converges to 0? You have an = 0 in the title.
 
  • #3
Mark44 said:
The rest of your thought is
For all n >= n0, ##\sqrt{a_n} < \epsilon##.

What are the given conditions? Is it an converges to 0? You have an = 0 in the title.

Yes it converges to zero
 
  • #4
Can you prove that sqrt(an) is eventually less than 1/100 ?

How about that sqrt(an) is eventually less than 1/(1000000) ?
 
  • #5


I understand the importance of being thorough and precise in our mathematical proofs. In this case, we are trying to prove that √a(n) converges to 0, which means that as n approaches infinity, the value of √a(n) gets closer and closer to 0.

To start, we can use the definition of convergence to help guide our proof. We know that for a sequence to converge to a limit L, we must have that for any small positive number ε, there exists a positive integer N such that for all n ≥ N, the absolute value of the difference between a(n) and L is less than ε.

In this case, our limit L is 0, so we can rewrite our definition as: for any small positive number ε, there exists a positive integer N such that for all n ≥ N, the absolute value of √a(n) is less than ε.

Now, let's use the fact that a(n) converges to 0. This means that for any small positive number ε, there exists a positive integer n0 such that for all n ≥ n0, the absolute value of a(n) is less than ε^2. We can rewrite this as: for any small positive number ε, there exists a positive integer n0 such that for all n ≥ n0, the absolute value of a(n) is less than ε^2.

Since we are trying to prove that √a(n) converges to 0, we can use the definition of convergence to rewrite this as: for any small positive number ε, there exists a positive integer n0 such that for all n ≥ n0, the absolute value of √a(n) is less than √(ε^2).

Now, we can simplify this to: for any small positive number ε, there exists a positive integer n0 such that for all n ≥ n0, the absolute value of √a(n) is less than ε.

This is exactly what we were trying to prove! We have shown that for any small positive number ε, there exists a positive integer n0 such that for all n ≥ n0, the absolute value of √a(n) is less than ε, which is the definition of convergence to 0.

Therefore, we have proven that √a(n) converges to 0. I hope this helps you with your proof.
 

Related to Prove √a(n) Converges to 0 | Stuck on Proof

What does it mean for √a(n) to converge to 0?

Convergence to 0 means that as the value of n increases, the value of √a(n) gets closer and closer to 0. In other words, the limit of √a(n) as n approaches infinity is 0.

Why is it important to prove that √a(n) converges to 0?

Proving that √a(n) converges to 0 is important because it shows that the sequence is approaching a specific value, rather than getting larger or smaller without a clear pattern. This can be useful in various mathematical and scientific applications.

What is the process for proving that √a(n) converges to 0?

The process for proving that √a(n) converges to 0 is by using the definition of convergence. This involves showing that for any given small number ε (epsilon), there exists a corresponding number N such that for all n greater than N, |√a(n) - 0| < ε. This essentially means that as n gets larger, the difference between √a(n) and 0 becomes smaller than any desired value ε.

Can there be cases where √a(n) does not converge to 0?

Yes, there can be cases where √a(n) does not converge to 0. If the sequence √a(n) does not approach a specific value or if the limit as n approaches infinity does not exist, then √a(n) does not converge to 0.

What are some common mistakes when trying to prove √a(n) converges to 0?

Some common mistakes when trying to prove √a(n) converges to 0 include not using the correct definition of convergence, not considering all possible values of n, and not clearly explaining each step of the proof. It is important to be thorough and precise in the proof to avoid these mistakes.

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