Transformation In modulus

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KingRich
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#1
Report Thread starter 1 month ago
#1
I have come across something similar to this question before.

Solve equation
x|x|=x²

So, first of all, cancel out x from both sides

I now have |x|=x

Therefore, -x= x and x=x
So,

-x=x ——> 0=2x , therefore x=0 and then x=x, well just cancels out.

Eh, what’s going on here lol

What’s to solve?
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mqb2766
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#2
Report 1 month ago
#2
(Original post by KingRich)
I have come across something similar to this question before.

Solve equation
x|x|=x²

So, first of all, cancel out x from both sides

I now have |x|=x

Therefore, -x= x and x=x
So,

-x=x ——> 0=2x , therefore x=0 and then x=x, well just cancels out.

Eh, what’s going on here lol

What’s to solve?
The 11th commandment. Factorize, don't divide (not much different here, but its clearer)
x(|x| - x) = 0
So
x=0
and
x = |x|
so all x>=0 solve that equation as should be fairly obvious from the question.
Last edited by mqb2766; 1 month ago
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