Proof by Contradiction || Prove that an equation can never be a square number

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Discussion Overview

The discussion revolves around the problem of proving that the expression n^2 + n + 1 can never be a square number for any integer n. The scope includes homework-related reasoning and attempts at mathematical proof.

Discussion Character

  • Homework-related, Mathematical reasoning, Debate/contested

Main Points Raised

  • One participant suggests using the quadratic formula to show that n cannot be an integer, but finds the solution too messy to prove definitively.
  • Another participant argues that the statement is false by providing a counterexample with n = -1, where the expression equals 1, which is a square number.
  • A later reply clarifies that the original question intended to refer to positive integers only.
  • There is a suggestion for editing posts, with participants discussing the limitations on editing time.
  • One participant indicates that the problem is resolved and suggests closing the thread.

Areas of Agreement / Disagreement

Participants disagree on the validity of the original statement, with one providing a counterexample that challenges the claim. The discussion remains unresolved regarding the proof for positive integers specifically.

Contextual Notes

The initial claim lacks clarity on the scope of integers (positive vs. negative), which affects the validity of the proof attempt. There are also unresolved mathematical steps in the proposed solution.

haxan7
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Homework Statement



Prove that for any integer n n^2+n+1, can never be a square number.


Homework Equations


None.


The Attempt at a Solution


We could put the equation to a^2, (where a^2 is a square number) and solve for n and show that n can not be an integer.
I tried quadratic formula on the equation but the solution gets too messy, and i can't prove that the answer is not an integer.
There must be an easier way to solve this. Just point me in the right direction.
 
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haxan7 said:

Homework Statement



Prove that for any integer n n^2+n+1, can never be a square number.

That's going to be very hard to prove, as it isn't true: (-1)2+(-1)+1=1=(1)^2
 
gabbagabbahey said:
That's going to be very hard to prove, as it isn't true: (-1)2+(-1)+1=1=(1)^2

Sorry, the question was "for any positive integer n", how do i edit the thread?
 
There should just be a button that says edit in the bottom right of your post.
 
tainted said:
There should just be a button that says edit in the bottom right of your post.

You can't edit your posts after 700 minutes.
 
Problem Solved, close this thread.
 

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