How to Describe a Set Using Calculus?

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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