Suppose that d 0 or 1 (mod 4) and that d is not a perfect square. Then d is called a fundamental discriminant if all binary quadratic forms of discriminant d are primitive. Show that if d 1 (mod 4) then d is a fundamental discriminant if and only if d is square free. Show that if d 0 (mod 4) then d is a fundamental discriminant if and only if d/4 is square-free and d/4 2 or 3 (mod 4).