Limits of Sequences .... Stoll Theorem 2.2.6

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SUMMARY

The discussion centers on the proof of parts (a) and (b) of Theorem 2.2.6 from Manfred Stoll's "Introduction to Real Analysis," specifically regarding the limits of certain special sequences. Peter proposes a proof strategy to demonstrate that the limit as \( n \) approaches infinity of \( \frac{1}{n^p} \) equals 0, using the epsilon-delta definition of limits. The community confirms his approach, emphasizing the importance of understanding the foundational axioms and definitions of real numbers to solidify the proof process.

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In his book: Introduction to Real Analysis, Manfred Stoll does not prove parts (a) and (b) of Theorem 2.2.6 on the limits to certain special sequences ...

I am having trouble getting started on the proof of part (a) ... can someone please help me to make a meaningful start to the proof ... (despite the fact that Stoll informs us that the proof is straightforward ... :( ... )

Theorem 2.2.6 reads as follows:

View attachment 7194Peter
 
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Peter said:
In his book: Introduction to Real Analysis, Manfred Stoll does not prove parts (a) and (b) of Theorem 2.2.6 on the limits to certain special sequences ...

I am having trouble getting started on the proof of part (a) ... can someone please help me to make a meaningful start to the proof ... (despite the fact that Stoll informs us that the proof is straightforward ... :( ... )

Theorem 2.2.6 reads as follows:

Peter

After some reflection I have a proposed solution ...To show $$\text{lim}_{ n \rightarrow \infty } = 0$$ Now ... for any $$\epsilon \gt 0$$ the inequality $$\left\lvert\frac{1}{ n^p } - 0\right\rvert \lt \epsilon$$gives $$\frac{1}{ n^p } \lt \epsilon$$ or $$n \gt \frac{1}{ \epsilon^{ \frac{1}{ p } }}$$ ... ... Hence ... if we take $$N \gt \frac{1}{ \epsilon^{ \frac{1}{ p } } } $$ ... then for $$n \gt N$$ we have ...$$\frac{1}{ n^p } \lt \left(\frac{1}{ \frac{1}{ \epsilon^{ \frac{1}{p} } } }\right)^p = \epsilon $$Is that correct?

Peter
 
Last edited:
Peter said:
After some reflection I have a proposed solution ...To show $$\text{lim}_{ n \rightarrow \infty } = 0$$ Now ... for any $$\epsilon \gt 0$$ the inequality $$\left\lvert\frac{1}{ n^p } - 0\right\rvert \lt \epsilon$$gives $$\frac{1}{ n^p } \lt \epsilon$$ or $$n \gt \frac{1}{ \epsilon^{ \frac{1}{ p } }}$$ ... ... Hence ... if we take $$N \gt \frac{1}{ \epsilon^{ \frac{1}{ p } } } $$ ... then for $$n \gt N$$ we have ...$$\frac{1}{ n^p } \lt \left(\frac{1}{ \frac{1}{ \epsilon^{ \frac{1}{p} } } }\right)^p = \epsilon $$Is that correct?

Peter
Yes! (Yes)
 
Opalg said:
Yes! (Yes)
Thanks Opalg ... it gives me great confidence when you or Evgeny confirm my effort ...

Thank you ...

Peter
 
Peter said:
After some reflection I have a proposed solution ...To show $$\text{lim}_{ n \rightarrow \infty } = 0$$ Now ... for any $$\epsilon \gt 0$$ the inequality $$\left\lvert\frac{1}{ n^p } - 0\right\rvert \lt \epsilon$$gives $$\frac{1}{ n^p } \lt \epsilon$$ or $$n \gt \frac{1}{ \epsilon^{ \frac{1}{ p } }}$$ ... ... Hence ... if we take $$N \gt \frac{1}{ \epsilon^{ \frac{1}{ p } } } $$ ... then for $$n \gt N$$ we have ...$$\frac{1}{ n^p } \lt \left(\frac{1}{ \frac{1}{ \epsilon^{ \frac{1}{p} } } }\right)^p = \epsilon $$Is that correct?

Peter

In going from: $$\frac{1}{ n^p } \lt \epsilon$$ to

$$n \gt \frac{1}{ \epsilon^{ \frac{1}{ p } }}$$

What are the axioms or theorems or definitions of the real Nos that you use??
 

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