Number Theory
# Quadratic Residues

Is 5 a quadratic residue modulo 7?

Which of these is the set of non-quadratic residues modulo \(11\)?

Which of these is the set of quadratic residues modulo \(15\)?

Find the sum of all positive integers \(x<22 \) such that \(x^2 \equiv 17 \pmod {22} \).

Is \(15\) a quadratic residue modulo \(17\)?