$\"\"$

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The identity is $\"\"$ .

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Consider $\"\"$ .

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$\"\"$

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Substitute $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$ .

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$\"\"$

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Solve $\"\"$ .

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The solutions of quadratic equation $\"\"$ are $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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Apply natural logarithm on each side.

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$\"\"$

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$\"\"$

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Substitute $\"\"$ .

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$\"\"$ .

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$\"\"$

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$\"\"$ .