Is Sqrt(x^2) Always Equal to |x|?

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SUMMARY

The discussion clarifies that the expression sqrt(x^2) is always equal to |x|, not simply x. This is due to the definition of the square root function, which returns the principal (positive) root. The example of plugging in -10 demonstrates that while x is negative, sqrt(x^2) yields a positive result, specifically 10. The distinction between sqrt(x^2) and |x| is crucial for understanding the behavior of these mathematical functions.

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TyErd
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Okay, when I enter into the calculator sqrt(x^2) it equals |x|. Since when? I thought sqrt(x^2) equals x and then when you go to sketch it, it will be a positive diagonal line through the origin whereas |x| is a reflection at the origin.
 
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A number squared is always positive. So if you plug in -10 you get sqrt(100) which is 10.
When you cancel out the square and the square root in a problem you do that because you're looking for the principle root aka the positive one.
 

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