Question
A vertical flagstaff stands on a horizontal plane. From
a point distant 210 metres from its foot, the angle of elevation of its top is found to be 30°. Find the height of the flagstaff.Solution
tan 30° = H/210 1/ 1/√3 = H/210 H = 210/ √3 × √3/√3 = √3 × 210/3 = 70√3 m
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