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Homework Statement
The problem is: Draw the graph of the following function:
f(x)=|x+|x+|x-1|||
Homework Equations
|x|=\left\{\begin{array}{cc}x,&\mbox{ if } x \geq 0\\-x,&\mbox{ if }x<0\end{array}\right
The Attempt at a Solution
If the function were, for instance, g(x)=|x+1|-|x-1|, the solution wouldn't be a problem, because the two important points (x=-1 and x=1) can be recognized immediately, which implies analysing the three intervals (<-\infty,-1> , [-1,1> , [1,+\infty>), and therefore the function g(x) can be seen as a compound of three different "sub-functions" on those intervals, ie:
g(x)=\left\{\begin{array}{ll}<br /> g(x)=-2,&\mbox{ if } x \in <-\infty,-1>\\<br /> g(x)=2x,&\mbox{ if }x \in [-1,1>\\<br /> g(x)=2,&\mbox{ if }x \in [1,+\infty>\end{array}\right
and as such, its graph can be easily drawn.
The same should be done for f(x)=|x+|x+|x-1|||. But how? Where to start? If starting from the "inside", there would be, at the first step, two cases: x-1\geq 0 or x-1<0, which would lead to more sub-cases, so I'm not sure if this is the right approach to arrive at the graph of f(x).
Any help would be much appreciated.