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Question
An aeroplane takes off at angle of `30^circ` with the ground . Find the height of the aeroplane above the ground when it has travelled 386m without changing direction .
Solution
The plane takes off from point C on the ground . Let A be the final position of the plane .
In ΔABC
`"AB"/"AC"` = `sin30^circ`
`"AB"/386 = 1/2`
`h = 386/2 = 193`
Thus , the required height of the aeroplane above the ground is 193 m .
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