Having a hard time understanding this

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Discussion Overview

The discussion revolves around a mathematical problem involving inequalities and the conditions under which they hold. Participants are tasked with proving a statement about the relationship between variables m, c, and k without using logarithms, exponents, or calculus, focusing instead on properties of real numbers.

Discussion Character

  • Homework-related
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant suggests that the problem presents two different questions and argues that the first hypothesis is not true due to a counter-example, while the second part could be proven using induction.
  • Another participant proposes using induction to approach the proof, noting the awkward wording of the question.
  • Several participants express confusion regarding the interpretation of the question, clarifying that it is a single question about the existence of c given m, rather than a universal statement for all m > 1.
  • One participant questions whether their initial interpretation was incorrect based on the clarification provided by others.

Areas of Agreement / Disagreement

Participants generally agree that the question is somewhat ambiguous and that it can be interpreted in different ways. There is no consensus on the validity of the initial hypothesis or the approach to the proof.

Contextual Notes

Participants highlight the potential confusion arising from the wording of the problem, which may lead to different interpretations regarding the conditions for m and c.

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bins4wins said:
Prove that if ##m > 1## such that there exists a ##c > 1## that satisfies
$$cm < m^c$$
then for any ##k > c##
$$km < m^k$$
holds. Prove this without using logarithms or exponents or calculus. Basically using the properties of real numbers to prove this.

This question was posted in the homework forum. To my understanding, this looks like two different questions as the first hypothesis is not true due to a simple counter-example argument. The second one would be true by two induction arguments on k>2 and k<0.

Am I wrong in thinking this? It seems logical since he said "there exists a c >1" so I would figure any REAL c must make the inequality true?
 
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I would use induction on this. The wording is pretty awkward and it seems like two different questions but I think they are looking for an induction type proof.
 
Zondrina, I had the same confusion as you when I first read the question. It is actually only one question. The first part is not saying
" if m>1 then there exists a c>1 that satisfies
cm<mc"
The whole thing is saying that if the number "m" is such that some "c" exists satisfying the requirement, then every k>c satisfies the second inequality.
 
LeonhardEuler said:
Zondrina, I had the same confusion as you when I first read the question. It is actually only one question. The first part is not saying
" if m>1 then there exists a c>1 that satisfies
cm<mc"
The whole thing is saying that if the number "m" is such that some "c" exists satisfying the requirement, then every k>c satisfies the second inequality.

Yes this makes sense now, thank you. If that were the case though, would I have been wrong to say that?

I thought he meant for every m>1, there exists a c>1 which satisfies .. blah.
 

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