Is |x|⋅|x|=|x2|=x2 ?
I'm very sorry if this question is a duplicate but I couldn't find anything about it (most likely because it's wrong..). But I'm not sure if this is correct so I need to ask you.
|x|⋅|x|=|x2| should be alright
Now my confusion starts. x2 should be positive / neutral for any value. That would mean we can ignore the absolute value sign? On the other hand we could have that |−x2|. But that would be a different thing than |x2|, they are not equal to each other...? Please help me if I do this little thing wrong the entire task will be wrong. I got some thinking error here..
When there is the same question (I couldn't find one), please link me to it and I will delete this one immediately.
Answer
You are thinking it too hard. You could just look at the definition of the absolute value
|x|:={x,x≥0−x,x<0
and check on your own that |x|2=|x2|=x2.
In general, we have |a|⋅|b|=|ab|, which is true also for complex numbers; but the identity |x2|=x2 is not necessarily true in the complex world.
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