$\"\"$

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$\"\"$ , $\"\"$ .

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$\"\"$ , $\"\"$ .

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Consider $\"\"$ , $\"\"$ .

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$\"\"$ .

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Let $\"\"$ and $\"\"$ place $\"\"$ in fourth quadrant.

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The point $\"\"$ is on a circle of radius $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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The $\"\"$ in fourth quadrant, therefore $\"\"$ .

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$\"\"$ .

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$\"\"$ .

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$\"\"$

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Consider $\"\"$ , $\"\"$ .

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The angle $\"\"$ is in first quadrant.

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$\"\"$ .

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

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The point $\"\"$ is on a circle of radius $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$ .

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$\"\"$ .

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$\"\"$ .

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$\"\"$

\

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(a) Find $\"\"$ .

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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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$\"\"$

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(b) Find $\"\"$ .

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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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$\"\"$

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(c) Find $\"\"$ .

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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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$\"\"$

\

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(d) Find $\"\"$ .

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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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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$ .

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$\"\"$ .

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$\"\"$

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(a) $\"\"$ .

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(b) $\"\"$ .

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(c) $\"\"$ .

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(d) $\"\"$ .