If x is even then is odd.
If x is odd then is also odd.
So it can't be zero.
Prove that if u is an odd integer, then the equation x^2 + x - u=0 has no solution that is an integer.
You can do this one of two ways, proof by contra positive, or proof by contradiction. I am a little confused on how I want to approach this.
If anyone has any insight, I would be more than appreciative. Thanks in advance.