MHB Absolute Value: Solve for x | MHB

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The equation to solve is ||x|-2|+|x+1|=3, with proposed solutions x=0, -2, 2, and -1. The discussion emphasizes the importance of considering different cases for x, such as x<-2, -2<x<-1, -1<x<0, 0<x<2, and x>2. Participants clarify that checking the boundaries is crucial, especially around x=-1, where |x+1| behaves differently. Ultimately, one participant confirms they found the correct answer after considering these cases.
Petrus
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Hello MHB,
solve $$||x|-2|+|x+1|=3$$
and we find that $$x=0,-2,2,-1$$
I got problem to find the 'case',

Regards,
$$|\rangle$$
 
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Petrus said:
Hello MHB,
solve $$||x|-2|+|x+1|=3$$
and we find that $$x=0,-2,2,-1$$
I got problem to find the 'case',

Regards,
$$|\rangle$$

That doesn't look like the right solution...

Talking about cases, what if x<-2? Or -2<x<-1? And what about -1<x<0? Or perhaps 0<x<2? And x>2?
 
I like Serena said:
That doesn't look like the right solution...

Talking about cases, what if x<-2? Or -2<x<-1? And what about -1<x<0? Or perhaps 0<x<2? And x>2?
I don't mean those are the answer, but those are the point we should check $$\geq$$ or $$\leq$$, I hope you did understand.
Can I also check this one insted of -1<x<0
-2<x<0?

Regards,
$$|\rangle$$
 
Petrus said:
I don't mean those are the answer, but those are the point we should check $$\geq$$ or $$\leq$$, I hope you did understand.
Can I also check this one insted of -1<x<0
-2<x<0?

Sure you can. It's just that |x+1| does something funny at x=-1.
 
I like Serena said:
Sure you can. It's just that |x+1| does something funny at x=-1.
Thanks, got the correct answer now :)
Regards,
$$|\rangle$$
 
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