Prove by Induction that n ≥ 2^(n-1) n ≥ 1

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Discussion Overview

The discussion revolves around proving the inequality n! ≥ 2^(n-1) for n ≥ 1 using mathematical induction. Participants explore the steps involved in the proof and seek assistance in completing the induction process.

Discussion Character

  • Homework-related
  • Mathematical reasoning

Main Points Raised

  • One participant states they have proven the base case for n=1 and the inductive step for n=k, where k! ≥ 2^(k-1) is assumed to be true.
  • The same participant expresses uncertainty about how to complete the proof for n=k+1, specifically questioning how to manipulate the inequality (k!)(k+1) ≥ 2^[(k+1)-1].
  • Another participant offers a hint suggesting that if an equation is true, multiplying both sides by the same factor will maintain the truth of the equation.

Areas of Agreement / Disagreement

The discussion remains unresolved, with participants not reaching a consensus on the proof for n=k+1 and differing levels of understanding about the induction process.

Contextual Notes

Participants have not fully articulated the assumptions or definitions used in their proofs, and there are unresolved steps in the mathematical reasoning presented.

kudzie adore
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prove by Induction that n! ≥ 2^(n-1) n ≥ 1
 
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Okay, so show us what you have attempted.
 
I managed to prove for n= 1 and is true
for n=k k!≥ 2^ (k-1) and I assumed that n=k to be true

then for n= k+1 its (k+1)! ≥ 2^[(k+1)-1]
proof for n=(k+1)

(k!)(k+1) ≥ _____?


the problem is that how do we reach the proof for (k+1)
 
hi kudzie adore! welcome to pf! :smile:

(try using the X2 button just above the Reply box :wink:)

hint: if an equation is true, then multiplying both sides by the same factor will still be true :wink:
 

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