Hello everyone,

I'd like to know how Ansys computes the stiffness matrix at point x1 in figure. I'm studying the way in which Ansys uses the Newton-Raphson method when there are nonlinearities.

In the slide there is the specification that we don't know the real curve F-x, thus I have some problem to understand which slope is taken at x1 by Ansys.

Thank you so much for your time.