Practice Example 1.27: Height Calculation Of A Lighthouse (1.9)

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5 sample questions

Question 1.
What is an angle of depression?
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Think about how you would describe looking down at something.
Question 2.
What does cotangent of an angle represent?
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Recall how tangent is the opposite over adjacent.
3Question 3.
What is the height of a lighthouse if the angles of depression to two ships are 30° and 45°?
- 40 m
- 50 m
- 60 m
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Calculate using Height = 100 / (cot(30°) - cot(45°)).
4Question 4.
True or False: The angle of depression is always measured upward from horizontal.
- True
- False
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Think about how you observe objects below.
Question 5.
From the top of a tower, the angles of depression to two points on the ground are 20° and 50°; if they are 150 m apart, find the height of the tower.
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Break down the angles and distances before calculating the difference.

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