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प्रश्न
The angle of elevation from a point P of the top of a tower QR, 50 m high is 60o and that of the tower PT from a point Q is 30°. Find the height of the tower PT, correct to the nearest metre
उत्तर
In ΔPQR
`tan 60^@ = (RQ)/(PQ)`
`sqrt3 = 50/(PQ)`
`PQ = 50/sqrt3`
In ΔPQT
`tan 30^@ = (PT)/(PQ)`
`1/sqrt3 = (PT)/(50/sqrt3)`
`PT = 1/sqrt3 xx 50/sqrt3 = 50/3`
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