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Example 5
Due to heavy wind a tree is broken. The length
of the broken part is 20 m. If the broken part makes an angle of
230 with the ground, find the original height of the
tree and distance of the end of the broken part from its trunk.
Solution : From the fig. sin 230 = 
\ 0.39 = AB \
AB = (0.39) (20) = 7.8 m.
\ Height of the unbroken tree = 20
+ 7.8 m = 27.8 m
Again cos 23 =  \
0.92 = AD \ AD = (0.92) (20)
\ AD = 18.4m.
\ The distance of end of the broken
tree from its trunk is 18.4m.
Example 6
When observed from an aeroplane, flying 2 km high,
at a certain moment the angle of depression of the top and bottom
of a building are 600 and 700 resp. Find the
high of the building.
Solution : Let the height of the building be x
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