Induction proof verification ##2^{n+2} < (n+1)## for all n ##\geq 6##

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Homework Help Overview

The discussion revolves around proving the inequality \(2^{n+2} < (n+1)!\) for all \(n \geq 6\) using mathematical induction. Participants are examining the validity of the induction steps and the behavior of both sides of the inequality as \(n\) increases.

Discussion Character

  • Exploratory, Mathematical reasoning, Assumption checking

Approaches and Questions Raised

  • Participants discuss the base case for \(n = 6\) and the assumption for the induction step. There is a mention of the inequality holding for values of \(n\) greater than 6, prompting questions about the general behavior of the inequality as \(n\) increases.

Discussion Status

Some participants express confidence in the approach, while others point out that \(n = 6\) is not the first instance where the inequality holds. The discussion is ongoing, with various interpretations being explored regarding the growth of the factorial compared to the exponential function.

Contextual Notes

There is a note about the formatting of LaTeX in the forum, indicating that participants are encouraged to use specific symbols for clarity in mathematical expressions.

ciencero
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$2^{n+2} < (n+1)!$ for all n $\geq 6$

Step 1: For n = 6,

$256 < 5040$.

We assume

$2^{k+2} < (k+1)!$

Induction step:

$2 * 2^{k+2} < 2*(k+1)!$

By noting $2*(k+1)! < (k+2)!$

Then $2^{k+3} < (k+2)!$
 
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Looks fine.
n=6 is not the first place where the inequality is true, by the way.
 
ciencero said:
$2^{n+2} < (n+1)!$ for all n $\geq 6$

Step 1: For n = 6,

$256 < 5040$.

We assume

$2^{k+2} < (k+1)!$

Induction step:

$2 * 2^{k+2} < 2*(k+1)!$

By noting $2*(k+1)! < (k+2)!$

Then $2^{k+3} < (k+2)!$
@ciencero, at this site, use double $ characters at each end for standalone LaTeX, or double # characters at each end for inline LaTeX.
 
It seems clear the RH side will eventually dominate. LH is being multiplied by 2 from nth to (n+1)st term while RH side is being multiplied by increasingly larger factors.
 

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