In the proof of the fact that Newton-Raphson is a second order numerical method they use a Taylor-sequence.
Iterative formula for Newton-Raphson:
$x_n=x_{n-1} - \frac{F(x_{n-1})}{F'(x_{n-1})}$
Why is there a factor $F''(\xi_{n-1})$ with $\xi_{n-1}$ between $\alpha$ and $x_{n-1}$ in the third term?
