$\"\"$

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The differential equation is $\"\"$ .

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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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$\"\"$

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Apply integration on each side.

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$\"\"$

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Let $\"\"$ , then $\"\"$ .

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$\"\"$

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Apply formula : $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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Replace $\"\"$ with $\"\"$ .

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$\"\"$

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$\"\"$

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Therefore, $\"\"$ .

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$\"\"$

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$\"\"$ .