# Math Help - function graph

1. ## function graph

f(x)=lxl+lx-1l
is it right to convert it to
f(x)=l2x-1l
is that right or wroung i know it is a stupid question but i really need an answer to it

2. Originally Posted by mohamedsafy
f(x)=lxl+lx-1l
is it right to convert it to
f(x)=l2x-1l
is that right or wroung i know it is a stupid question but i really need an answer to it
No. They are different on the interval $(0,1)$. If you substitute say $x = \frac{1}{2}$ in each, the answers will be different

3. Originally Posted by danny arrigo
No. They are different on the interval $(0,1)$. If you substitute say $x = \frac{1}{2}$ in each, the answers will be different
are you sure cause if i subtitute in the first one with 1/2 the answer will be 0 and if i subtitute in the second one with 1/2 the answerwill be 0

4. Originally Posted by mohamedsafy
f(x)=lxl+lx-1l
is it right to convert it to
f(x)=l2x-1l
is that right or wroung i know it is a stupid question but i really need an answer to it
Use the definition of the absoluet value. You'll get three intervals with different terms:

$|x|+|x-1| = \left\{\begin{array}{ll}-2x+1 & if\ x<0\\1& if\ 0\leq x<1 \\ 2x-1& if\ x\geq 1\end{array}\right.$

5. Originally Posted by mohamedsafy
are you sure cause if i subtitute in the first one with 1/2 the answer will be 0 and if i subtitute in the second one with 1/2 the answerwill be 0
$|\frac{1}{2}| + | \frac{1}{2} - 1 | = |\frac{1}{2}| + | -\frac{1}{2} | = |\frac{1}{2}| + | \frac{1}{2} | = 1$