$\"\"$

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A person in a boat offshore from a vertical clift is $\"\"$ in height.

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The angle of elevation is $\"\"$

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$\"\"$

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Observe the figure : $\"\"$ and $\"\"$ .

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For a right angle triangle :

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

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Consider the trigonometric functions: $\"\"$ and $\"\"$ .

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

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$\"\"$

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$\"\"$

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$\"\"$

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Therefore, $\"\"$ .

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$\"\"$

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Find Distance between $\"\"$ and $\"\"$ .

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$\"\"$ is adjacent side of the right angle triangle.

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So, $\"\"$ .

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

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$\"\"$

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$\"\"$

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$\"\"$

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Distance from offshore to boat $\"\"$ .

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$\"\"$

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Distance from offshore to boat is $\"\"$ .