How to Describe a Set Using Calculus?

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SUMMARY

The discussion focuses on solving the inequality set {x: |x² - 5| < 4}. The correct approach involves manipulating the absolute value inequality into a double inequality: -4 < x² - 5 < 4. This leads to the conclusion that 1 < x² < 9, which simplifies to two intervals: 1 < x < 3 and -3 < x < -1. The solution set is thus comprised of these two intervals, confirming that the problem requires identifying both positive and negative solutions.

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Homework Statement



Describe the set {x:|x2-5|<4}


Homework Equations





The Attempt at a Solution



I know this is simple stuff but I'm confused as to what way I'm supposed to answer this.

My current answer is:

|x2-5|<4
-4<x2-5<4
-4+5<x2<4+5
1<x2<9
1<x<3

Is that all the question asks for? Do I need to say anything else?
 
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If [itex]1< x^2< 9[/itex] then either [itex]1< x< 3[/itex] or [itex]1< -x< 3[/itex] so the solution set is two intervals.
 
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Ok thanks for the help HallsofIvy
 

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