How can I prove this using the remainder theorem?

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    Proof Remainder Theory
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Discussion Overview

The discussion revolves around proving that if \( p^2 \) is exactly divisible by \( p+q \), then \( q^2 \) is also exactly divisible by \( p+q \). Participants explore the application of the remainder theorem and various algebraic manipulations to establish this relationship.

Discussion Character

  • Mathematical reasoning
  • Debate/contested

Main Points Raised

  • One participant proposes that if \( p^2 \) is divisible by \( p+q \), then \( q^2 \) should also be divisible by \( p+q \), seeking a proof using the remainder theorem.
  • Another participant suggests considering the expansion of \( (p+q)^2 = p^2 + 2pq + q^2 \) as a potential approach.
  • A participant attempts to manipulate the expression by letting \( p^2 = x^2 + 2xy + y^2 \) and explores the implications of setting \( y = -x \), leading to the conclusion that \( p^2 = q^2 \) under certain conditions.
  • There is a correction regarding the expression of the modulus operation, with a later reply clarifying that it should be \( q^2 \mod (p+q) = 0 \).
  • Another participant expresses uncertainty about the correctness of their calculations and reasoning, questioning if there are flaws in their argument.

Areas of Agreement / Disagreement

Participants express differing views on the validity of the proposed proofs and calculations, with no consensus reached on the correctness of the arguments presented.

Contextual Notes

Some participants' arguments rely on specific algebraic manipulations and assumptions that may not be universally accepted or fully justified within the discussion.

Hyperreality
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If p^2 is exactly divisible by p+q, then proof q^2 is exactly divisible by p+q.

How do I proof this, and how do I apply the remainder theorem?

I know if f(x) = x^2 + 2x + 1, since f(-1) = 0 there fore (x + 1) is a factor of f(x).

So in this case
p^2 = p x p or p^2 x 1...
 
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Since you specifically mention x2+ 2x+ 1, haven't you looked at (p+q)<sup>2</sup>= p<sup>2</sup>+ 2pq+ q<sup>2</sup>?
 
This is what I've done afterwards, but I'm not sure if it is right.

Let p^2 = x^2 + 2xy + y^2.

where y^2 = y.y or -y.-y or x^2 = x.x or -x.-x.

When y = -x, or x = -y, p^2 = 0

Therefore (x + y) is a factor of p^2, also (x + y) = (p + q)

Therefore p^2 = p^2 + 2pq + p^2. p^2 = 0 when p = -q,

but (p)^2 = (-q)^2
p^2 = q^2
therefore (p+q)mod q^2 = 0

Are there any flaw in my argument or have I made any calcuation error?
 
Sorry, it's q^2mod(p+q) = 0
 
Originally posted by Hyperreality
This is what I've done afterwards, but I'm not sure if it is right.

Let p^2 = x^2 + 2xy + y^2.

where y^2 = y.y or -y.-y or x^2 = x.x or -x.-x.

When y = -x, or x = -y, p^2 = 0

Therefore (x + y) is a factor of p^2, also (x + y) = (p + q)

Therefore p^2 = p^2 + 2pq + p^2. p^2 = 0 when p = -q,

but (p)^2 = (-q)^2
p^2 = q^2
therefore (p+q)mod q^2 = 0

Are there any flaw in my argument or have I made any calcuation error?
p^2=P^2+2pq+q^2
-2pq=q^2
-2p=q
p=-q/2
not p=-q
 

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