utf06-009

A revolving beacon from a lighthouse shines on the straight shore, and the closest point on the shore is a pier one half mile from the lighthouse. Let $\theta$ denote the positive acute angle between the shore and the beam of light. Write the distance from the pier to the point where the light shines on the shore as a function of $\theta$.

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Tags: trig, geometry, v--a, classic, t1, c1

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This strange nub of a problem is obviously a foreshadowing of the related rates problems to come. It’s best used early in the class for a bit of a break and to make them not panic the next time they see lighthouse problems, etc.

– Eric Hsu 1998-08-09