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प्रश्न
A tower stands vertically on the ground. From a point on the ground which is 25 m away from the foot of the tower, the angle of elevation of the top of the tower is found to be 45°. Then the height (in meters) of the tower is
विकल्प
A. `25sqrt2`
B. `25sqrt3`
C. 25
D. 12.5
उत्तर
Let AB be the tower and C be the point on the ground 25 m away from the foot of the
tower such that ∠ACB = 45°.
In right ΔABC:
`tan 45 ^@=(AB)/(BC)`
`rArr l=(AB)/25m`
⇒ AB = 25 m
Thus, the height of the tower is 25 m.
The correct answer is C.
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