What is the extremum of the function z = x ^ 2-y ^ 2 + 1? A.(0,0) B.(0,1) C.(1,0)

What is the extremum of the function z = x ^ 2-y ^ 2 + 1? A.(0,0) B.(0,1) C.(1,0)

First, the partial derivatives of X and y are solved to obtain two equations, then x and y are solved to obtain the stationary point