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At what angle an observer observes a box...

At what angle an observer observes a box lying on ground from the roof fo three-storid building, so that the hight of building is equal to the distance of the box from the building ?

A

`15^(@)`

B

`30^(@)`

C

`45^(@)`

D

`60^(@)`

Text Solution

Verified by Experts

Let the box be at C on the ground and the obsever obsevers it from the point A of the roof of the building AB.
As per question, AB = BC, `"AE"abs()"BC"`,`therefore angleACB = angleACB = theta`(let).
`therefore` from the right-angled `DeltaABC` we get,
or, `tan theta = 1 ` or, `tan theta = tan 45^(@) " "rArr theta =45^(@)`.
Hence (c) correct.
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