Properties of Absolute Value with Two Abs Values

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Is it true that ##\frac{|a|}{|b|} = |\frac{a}{b}|## and ##|a| < |b| = a^2 < b^2##?
 
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askor said:
##|a| < |b| = a^2 < b^2##?

Do you mean ##|a| < |b| \iff a^2 < b^2##?
 
etotheipi said:
Do you mean ##|a| < |b| \iff a^2 < b^2##?

Yes.
 
Define ##|x| = \sqrt{x^2}##. Can you use certain properties of the square root to show that ##\frac{|a|}{|b|} = |\frac{a}{b}|##?
 
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romsofia said:
Define ##|x| = \sqrt{x^2}##. Can you use certain properties of the square root to show that ##\frac{|a|}{|b|} = |\frac{a}{b}|##?

I don't understand. Please tell me the point.
 
askor said:
I don't understand. Please tell me the point.
$$\frac{|a|}{|b|} = \frac{\sqrt{a^2}}{\sqrt{b^2}} = \sqrt{\frac{a^2}{b^2}} = \sqrt{\left(\frac{a}{b}\right)^2} = \dots$$