Disproving Statement: No Natural Numbers Satisfy y^5 + 1 = (x^7-1)/(x-1)

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Homework Help Overview

The discussion revolves around proving that there are no natural numbers x and y that satisfy the equation y^5 + 1 = (x^7 - 1)/(x - 1). Participants are exploring various mathematical approaches and reasoning related to this statement.

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning, Assumption checking

Approaches and Questions Raised

  • Participants have attempted to simplify the equation and explore its implications, questioning how factors relate to each other. There are discussions about the gcd of terms, the nature of prime factors, and the implications of coprimality.

Discussion Status

The discussion is active, with participants providing insights and questioning each other's reasoning. Some participants have suggested potential paths forward, while others express uncertainty about specific steps or theorems being referenced.

Contextual Notes

There are mentions of specific cases regarding the nature of x and c being fifth powers, and the implications of their coprimality. Participants are also considering the constraints of positive integer values in their reasoning.

  • #31
Faiq said:
I don't think its necessary for both to be a fifth power consider this
y5 = (ab)5 = a5.b5
C = a5.b
x = b4
y5 = cx = (a5.b)(b4) = a5.b5 =(ab)5
But then C and x wouldn't be coprime they would have common factor b.
 
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  • #32
Oh yeah right thanks
 
  • #33
Btw you are right about case 1 and 3 we just omitted them because they kind of intuitively obvious that they lead to contradiction.
 
  • #34
Thank you very much for the help
 
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