It is
interesting to calculate F¢(a) (see Aitkins.doc .htm for derivation of F') for
This does not mean that there is no error in the iterative
procedure, but does mean that we need to take it to a higher approximation so
that for
calculating the second derivative we find
the last term of which is zero for f(x)=0, but not the first two.
and hence we see the familiar quadratic convergence
associated with
10-2 on step 5, will be off by 10-4 ´ 10 =
10-3 on step 6 and by 10-5
on step 7.