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प्रश्न
A monkey is climbing a rope of length 15 m in a circus. The rope is tied to a vertical pole from its top. Find the height of the pole, if the angle, the rope makes with the ground level is equal to 60°.
उत्तर
The pole AB in the illustration is where the rope is attached from point C on the ground.
So, AC = 15 m, ∠ACB = 60°
Now, in ΔABC,
`(AB)/(AC)` = sin 60°
`(AB)/15 = sqrt(3)/2`
AB = `(15sqrt(3))/2`
AB = 12.99 m
As a result, the pole's height is 12.99 m.
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