Solving equations via substitution

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Discussion Overview

The discussion revolves around solving equations involving substitution, specifically in the context of Hamming codes. Participants explore the relationships between variables k, n, and c, and how to manipulate these equations to find the value of c.

Discussion Character

  • Exploratory
  • Mathematical reasoning
  • Homework-related

Main Points Raised

  • One participant presents the equation n = k + c with k = 7 and n = 2^c - 1, leading to the equation 7 + c = 2^c - 1, which simplifies to c = 2^c - 8.
  • The same participant expresses confusion as substituting c = 4 does not yield a correct answer.
  • Another participant suggests a potential modification to the problem, proposing that it should state n = k + 2c instead.
  • A third participant provides additional context by explaining that this discussion pertains to Hamming codes, where n represents the total number of bits, k the amount of information digits, and c the amount of check digits.
  • This participant also shares another example where n = 4 + c and n = 2^c - 1, leading to the equation 4 + c = 2^c - 1, which simplifies to c = 2^c - 5.
  • A later reply reiterates the context of Hamming codes and mentions an inequality found online: n ≤ 2^c - 1.

Areas of Agreement / Disagreement

Participants do not appear to reach a consensus on the correct formulation of the equations or the value of c, as multiple competing views and suggestions are presented.

Contextual Notes

There are unresolved assumptions regarding the definitions of n, k, and c, as well as the implications of the proposed changes to the equations. The discussion also reflects uncertainty about the correct application of Hamming code principles.

jackscholar
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I am trying to solve an equation that involves substitution.

I was given k= 7 in the equation n=k+c
i was also given n=2^c-1
I figured that 7+c could be substituted into the equation as n, so I got
7+c=2^c-1 and therefore c=2^c-8.
The problem is that the answer I want is c=4...but substituting 4 as C does not give me a correct answer. Any help would be greatly appreciated.
Thank you
 
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Maybe the probem should say n = k + 2c
 
This pertains to hamming codes, so n is the total number of bits, k is the amount of information digits and c is the amount of check digits. I was given another example aswell. This example says: Suppose there are four information digits.
Then n=4+c
and n=2^c-1
then 4+c=2^c-1
hence c=2^c-5
 
jackscholar said:
I was given k= 7 in the equation n=k+c
i was also given n=2^c-1
This pertains to hamming codes

The inequation I see on the web for hamming codes is [itex]n \le 2^c -1[/itex]
 

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