A basic function question - with a strange absolute value placement

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Homework Help Overview

The discussion revolves around a piecewise function defined by different expressions based on the value of x, specifically focusing on the significance of the absolute value in the middle segment of the function. Participants are exploring the implications of the absolute value on the function's definition and its domain.

Discussion Character

  • Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • The original poster attempts to understand the role of the absolute value in the function's definition and questions whether it indicates any undefined regions for the function. Other participants clarify the equivalence of the absolute value expression to a range of x values.

Discussion Status

The discussion has progressed with participants providing clarifications regarding the absolute value and its implications for the function's domain. The original poster acknowledges the helpfulness of the responses received.

Contextual Notes

There is a focus on understanding the implications of the piecewise function's definition, particularly regarding the absolute value and its effect on the intervals of x. The original poster's initial interpretation of the absolute value as potentially misleading is addressed through clarification.

latefreight
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Homework Statement



If f(x) is equal to...

x+9 if x<-3
-2x if |x|\leq 3
-6 if x > 32. The attempt at a solution

The first and third "segments" of when the function is defined as being x+9 and -6 are pretty straightforward to me, however I am unaware of the significance of the placement of the absolute value of x in the middle if statement of when the function is equal to -2x. Is it significant at all? Does this imply this function is undefined when -3 < x < 0? Or is it, as my initial hunch was, really just some type of a distraction?
 
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|x| <= 3 is equivalent to -3 <= x <= 3, so your hunch that this is a distraction is wrong.
 
<br /> 0 \le \left| x \right| \le a \; \Leftrightarrow \; -a \le x \le a<br />
 
Thank you. I didn't choose my word "distraction" cautiously enough. Since the statements you both posted are equivalent - that was indeed what I needed to know.
 

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