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The function is $\"\"$ .

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(a) Find $\"\"$ .

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The function $\"\"$ .

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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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The function is $\"\"$ .

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(b) Find $\"\"$ .

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$\"\"$

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$\"\"$

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

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$\"\"$

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Cross multiplication.

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$\"\"$

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$\"\"$ .

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(a) $\"\"$ .

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(b) $\"\"$ .