You can put this solution on YOUR website! It's called "absolute value".
It means that whatever is inside
the bars, you ignore the minus if it
has a minus sign. Therefore:
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You have:
Try , then not true
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If , true
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Try also not true
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But if , true
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If , then true
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What it boils down to is,
there are 2 ranges for
that make the inequality true:
and
Anything between and including and fails
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Hope this helps