Computing the hessian matrix

So I need to compute the gradient and hessian of a given equation. The sample equation is Y=2*X(1)^3+3*X(2)^2+X(3). I think I was able to get the gradient by using gradient(X,Y). However when I try using the hessian function I receive the error "Undefined function 'hessian' for input arguments of type 'double'." Thanks for the help

[Torsten]

Please show the code you are using and the error message you get.

Best wishes

Torsten.

[RAJ KUMAR]

 Use 
Y=2*X(1).^3+3*X(2).^2+X(3);
instead of 
Y=2*X(1)^3+3*X(2)^2+X(3);
I think you'll get what you want.

Raj