Rewrite

f$($x$)=|$x$|$

as a piecewise function for

x $<0$ and x $0.$

This will remove the absolute value sign.

Write

f$($x$)$

on the interval

$[1,0).$

f$($x$)=|$x$|$

$=$

$1$

$$

$=$

$1$

Write

f$($x$)$

on the interval

$[0,4).$