Allow f(x, y) = x² + kxy + y²where k is constant

For what values of k does the Second Derivative Test guarantee that f (x, y) will have a saddle point at the origin? k6 For what values of k does the Second Derivative Test guarantee that f (x, y) will have a local minimum at the origin? k6 For what values of k does the Second Derivative Test guarantee that f (x, y) will have a local maximum at the origin? k6 For what values of the constant k will the Second Derivative Test be inconclusive for f (x, y) at the origin? k6 Enter your answers using interval notation