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

AI Thread Summary
The discussion revolves around proving that the expression n^2+n+1 can never be a square number for any integer n. Initially, a user attempted to apply the quadratic formula but found the solutions too complex to demonstrate that n cannot be an integer. Another participant pointed out a flaw in the original statement, providing a counterexample with n = -1, which yields a square number. The user later clarified that the question pertains specifically to positive integers. The thread concludes with acknowledgment of the mistake and a suggestion to close the discussion.
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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