given the function $f(x,y,) = x^2-y^2$.
the gradient should be given by $grad f = (2x, -2y)$.
If I'm drawing single of these vectors, I only get the ones on the positive x-axis. Is this correct?
And what does the laplace operator tell me? In this case it is $f_{xx} + f_{yy} = 2-2 = 0$. So at ANY point of this function the divergence of the gradient is zero?
Thank you very much :)