$\"\"$

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

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Observe the graph: $\"\"$ , $\"\"$ , $\"\"$ and $\"\"$ .

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(a)

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Find $\"\"$ .

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$\"\"$

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Apply derivative on each side with respect to $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$ .

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Substitute $\"\"$ .

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$\"\"$

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

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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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(b)

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Find $\"\"$ .

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The function is $\"\"$ .

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Observe the graph: $\"\"$ and $\"\"$ does not exist.

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$\"\"$

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Apply derivative on each side with respect to $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$

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Substitute $\"\"$ .

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$\"\"$

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Substitute $\"\"$ .

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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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(a) $\"\"$ .

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(b) $\"\"$ .