Vector Algebra

Let \(x\) and \(y\) are real numbers. If \(\mathbf{a}=(\sin x) \hat{\mathbf{i}}+(\sin y) \hat{\mathbf{j}}\) and \(\mathbf{b}=(\cos x) \hat{\mathbf{i}}+(\cos y) \hat{\mathbf{j}}\), then \(|\mathbf{a} \times \mathbf{b}|\) is