When Newton's method doesn't work

Newton's method only works when
1) The function f(x) is smooth, and
2) Your initial guess was reasonably good.
If the function is rough, or if the initial guess was bad, then al bets are off.

[namibianbackyardengineerin]

Make sure:
1. That the function is differentiable.
2. That you don't devide by 0 with f'(x)
3. That your first guess is good.

[sadkacadmy]

how could i choose the intial point for non linear system is there asort of wayor method for doing that

[playlover]

so...if Newton's method doesn't work...which is the alternative?

[Vidrinskas]

The bottom line is... if you're not an idiot Newton's method will work.