How do I graph the absolute value function with multiple layers?

AI Thread Summary
To graph the function f(x)=|x+|x+|x-1|||, it's essential to analyze the absolute value layers step by step. Start by identifying critical points where the function changes, specifically at x=1 and x=-1, which will help in determining the intervals for analysis. The approach involves breaking down the function into simpler components, starting from the innermost absolute value and working outward. Evaluating specific values, such as f(10), can provide insight into the function's behavior in different regions. Understanding these key points and intervals will facilitate accurately sketching the graph of f(x).
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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,&amp;\mbox{ if } x \in &lt;-\infty,-1&gt;\\<br /> g(x)=2x,&amp;\mbox{ if }x \in [-1,1&gt;\\<br /> g(x)=2,&amp;\mbox{ if }x \in [1,+\infty&gt;\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&lt;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.
 
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Perhaps start by drawing x-1, then |x-1|, then x, then x+|x-1| etc.
Or else the method you describe is the only one I can think of.
 
First find the key points where the function changes. There are only 2 points where it changes. For example, plug in 10 for x.
f(x)=|10+|10+|10-1|||
f(x) = 29
the key points should not be that hard to find.
 
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