$\"\"$

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The functions are $\"\"$ and $\"\"$ .

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

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Consider $\"\"$ .

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$\"\"$

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

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$\"\"$

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$\"\"$

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Apply formula $\"\"$ .

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Let $\"\"$ is constant.

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$\"\"$ .

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

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Substitute $\"\"$ in $\"\"$ .

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$\"\"$

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

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$\"\"$

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$\"\"$

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$\"\"$ .

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Substitute $\"\"$ in $\"\"$ .

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$\"\"$ .

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$\"\"$

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$\"\"$ .