In: Advanced Math
For the following functions f and g : f(x, y) = e^ax − (1 − a)lny a > 0 g(x, y, z) = −3x^2 − 3y^2 − 3z^2 + 2xy + 2xz + 2yz
1. Calculate the Hessian matrices of f and g noted Hf (x, y) and Hg(x, y, z)
2. Show that Hg(x, y, z) is define negativly for all (x, y, z) ∈ Dg
3. For what value o a is , Hf (x, y) define positivly for any (x, y) ∈ Df ?