$\"\"$

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The expression is $\"\"$ .

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Substitute $\"\"$ in the above expression.

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$\"\"$

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$\"\"$

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$\"\"$ definition:

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$\"\"$ means that for every $\"\"$ , there exists a $\"\"$ , such that for every $\"\"$ , the expression $\"\"$ implies $\"\"$ .

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Consider $\"\"$

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$\"\"$

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Cubing on both sides.

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$\"\"$

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Consider $\"\"$

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$\"\"$

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$\"\"$

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Observe the relationship between two absolute values $\"\"$ and $\"\"$ .

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$\"\"$

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$\"\"$

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Therefore $\"\"$ . $\"\"$

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$\"\"$ and $\"\"$ .