3. (5 %) Consider these infinitely differentiable functions: g: RR, h: R* > R, and their composition function f(x)=gh(x) = g(h(x)). Use Chair rule to verify that the Hessian matrix of f(x) is f(x) = g" (h(x))Vh(x) (Vh(x))" + g'(h(x))Vh(x).