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The angle of elevation from a point on t...

The angle of elevation from a point on the bank of a river of the top of a temple on the other bank is `45^@`. Retreating 50 m, the observer finds the new angle of elevation as `30^@`. What is the width of the river ?

A

50m

B

`50 sqrt3 m`

C

`50/(sqrt3-1)m`

D

100m.

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MODERN PUBLICATION-TRIGNOMETRY-EXERCISE
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  15. x = sin theta cos theta, and y = sin theta +cos theta are satisfied by...

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  16. A man observes the elevation of a balloon to be 30^@. He then walks 1 ...

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  17. The number of integral values of k for which the equation 7 cos x + 5 ...

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