Newton method´s starting point

I took advantage of the user-easy implementation of the Newton method for a nonlinear problem:

solve(F == 0, r, bcu,solver_parameters={“newton_solver”:
{“relative_tolerance”: 1e-6}})

I was however wondering how the stating point is chosen? COuld you please held me?
Thanks in advance.

The initial guess is whatever is already contained in your Function, r.