One of the basic question from trigonometry (height and distance) in which we have been asked to find the width of the river if from a point on a bridge across a river, the angles of depressions of the banks on opposite sides of the river are 30∘ and 45∘, respectively. If the bridge is at a height of 2.5 m from the banks.
RS Aggarwal, Class 10, Chapter 14, question no 28
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