$\"\"$

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(a).

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The length of isolated triangle is $\"\"$ ,and the included angle is $\"\"$ .

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The height of triangle is $\"\"$ and the base of triangle is $\"\"$ .

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Hence $\"\"$

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$\"\"$

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$\"\"$

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Consider $\"\"$ .

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$\"\"$

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The area of triangle is $\"\"$ .

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Substitute $\"\"$ and $\"\"$ in the above equation.

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$\"\"$

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$\"\"$

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$\"\"$ .

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$\"\"$

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(b).

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If $\"\"$ is increasing at the rate of $\"\"$ radian per minute,hence $\"\"$ .

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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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The chain rule of derivative : $\"\"$ .

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$\"\"$

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Find $\"\"$ ,when the angle $\"\"$ .

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Substitute $\"\"$ and $\"\"$ in the above equation.

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$\"\"$

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$\"\"$

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$\"\"$

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Find $\"\"$ , when the angle $\"\"$ .

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Substitute $\"\"$ and $\"\"$ in the above equation.

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$\"\"$

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$\"\"$

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$\"\"$

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(c).

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If $\"\"$ constant,then $\"\"$ is proportional to $\"\"$ .

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Therfore area of the traingle is not constant even though $\"\"$ is constant.

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$\"\"$

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(a). $\"\"$ .

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(b). $\"\"$ and $\"\"$ .

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(c).If $\"\"$ constant,then $\"\"$ is proportional to $\"\"$ .