$\"\"$

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The function is $\"\"$ .

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(a).

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Find the value of $\"\"$ .

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$\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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Therefore, $\"\"$ .

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As the time $\"\"$ tends to $\"\"$ , the value of the velocity $\"\"$ is constant.

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$\"\"$

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( b).

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Use l $\"\"$ Hospital rule to find $\"\"$ .

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$\"\"$ .

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Evaluate of the limit.

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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L $\"\"$ Hospital $\"\"$ s Rule :

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If the value of limit is indeterminate form of type $\"\"$ or $\"\"$ , then

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$\"\"$

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$\"\"$

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Since $\"\"$ use L $\"\"$ Hospital $\"\"$ s rule.

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$ .

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Therefore , $\"\"$ .

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$\"\"$

\

(a). $\"\"$ .

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As the time $\"\"$ tends to $\"\"$ , the value of the velocity $\"\"$ is constant.

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(b). $\"\"$ .