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प्रश्न
The tops of two poles of height 20 m and 14 m are connected by a wire. If the wire makes an angle of 30° with horizontal, then the length of the wire is
विकल्प
12 m
10 m
8 m
6 m
उत्तर
Let h be the length of wire AB.
Given that wire makes an angle `∠B=30°`
Now, ,`AC=(20-14)cm=6 cm`
Here, we have to find length of wire.
So we use trigonometric ratios.
In a triangle,ABC
`⇒ sin B=(AC)/(AB)`
`⇒ sin 30°=6/h`
`⇒1/2=6/h`
`⇒h=12`
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