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प्रश्न
The angle of elevation of the top of a vertical cliff from a point 30 m away from the foot of the cliff is 60°. Find the height of the cliff.
उत्तर
Let AB be the diff and angle of elevation from point C (on ground) is 30 °.
In ΔABC
`("AB")/("BC") = tan60^circ`
`"AB"/30 = sqrt(3)`
AB = `30sqrt(3)` m
So , height of tower is `30sqrt(3)` m
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