From a light house the angles of depression of two ships on opposite sides of the light house are observed to be 30° and 45°. If the height of the light house is h metres, the distance between the ships is


Here AB is the light house of height h meters


The angles of depression from the light house are 30° and 45°


The distance between the two ships is CD


In Δ ABC


tan 45° =


BC = AB ( tan 45° = 1)


BC = h


In Δ ABD


tan 30° =



(h + CD) = √3 h (AB = BC = h)


CD = (√3 -1) h

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