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प्रश्न
Two persons are standing on the opposite sides of a tower. They observe the angles of elevation of the top of the tower to be 30° and 38° respectively. Find the distance between them, if the height of the tower is 50 m.
उत्तर
Two persons A and B are standing on the opposite side of the tower TR and height of tower TR = 50 m and angles of elevation with A and B are 30° and 38° respectively.
Let AR = x and RB = y
Now in right ΔTAR, we have
`tan theta = (TR)/(AR)`
`=> tan 30^circ = 50/x`
`=> 1/sqrt(3) = 50/x `
∴ `x = 50sqrt(3) = 86.60 m`
Again in right ΔTRB, we have
`tan 38^circ = 50/y`
`=>` y tan 38° = 50
`y = 50/tan 38^circ`
= `50/0.7813`
= 63.99
or 64.00 m ...(i)
∴ Distance between A and B
= x + y
= 86.60 + 64.00
= 150.6 m
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