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,
$$|\rangle$$
 
Here is a little puzzle from the book 100 Geometric Games by Pierre Berloquin. The side of a small square is one meter long and the side of a larger square one and a half meters long. One vertex of the large square is at the center of the small square. The side of the large square cuts two sides of the small square into one- third parts and two-thirds parts. What is the area where the squares overlap?

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