Quadratic residues solutions I have a homework question that I can't figure out. It says:
If the prime p > 5 , show that there are always two quadratic residues of p that differ by two

Note that $1$ and $4$ are QR. So if one of $2$ or $3$ is a QR, we are finished.
If both $2$ and $3$ are NR, then $6$ is a QR. But then $4$ and $6$ are QR that differ by $2$. 
