$We$ have

$xn+1=xn-$

$f(xn)$

$f\text{'}(xn)$

$=xn-$

$xn5-xn-4$

$5xn4-1$

$.$

Therefore, $we$ get the following. $(Round$ your final answer $to$ six decimal places.$)$

$x2=2-$

$79$

$=$