Absolute Value

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Absolute Value

by apple100 » Tue Apr 07, 2009 6:31 pm
1. 1 > |x^2|

2. 1 < |x^2|

3. 1 > |x|^2

4. 1 < |x|^2




How do you solve for x?

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by Ian Stewart » Tue Apr 07, 2009 7:05 pm
Since x^2 is never negative, x^2 = |x^2| = |x|^2. For each of the inequalities above, you can ignore the absolute value signs. So, for example, if |x|^2 < 1, that just means that -1 < x < 1.
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