 Solution

ID: past-exam-of-the-options-ii-course-of-the-university-of-oxford/2004/c/c2/a/i/solution

(\frac{a}{p}) = ⎩ ⎨ ⎧ 0, 1, - 1, p ∣ a, a is a nonzero square modulo p, a is a nonsquare modulo p .

The distinction between the zero class and a nonzero quadratic residue is essential.

 New to topics? Read the docs here!