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प्रश्न
A tower stands vertically on the ground. From a point on the ground, 20 m away from the foot of the tower, the angle of elevation of the top of the tower is 600. What is the height of the tower?
उत्तर
Let AC be the ladder of length, hm and C be the points, makes an angle of elevation 60° with the wall and foot of the ladder is 9.5 meters away from the wall.
In a triangle ABC, given that BC = 9.5 m and angle C = 60°
Now we have to find the length of the ladder.
So we use trigonometrically ratios.
In a triangle ABC,
`=> cos C = (BC)/(AC)`
`=> cos 60^@ = 9.5/h`
`=> 1/2 = 9.5/h`
`=> h = 19`
Hence length of ladder is 19 meters
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