Page 1 - Lesson Notes-Word Problems Ch-9 (Applications of Trigonometry)

SAI International School
Class X

Mathematics – Lesson Notes

Chapter 9- Some Applications of Trigonometry

Sub Topics – Problems on applications of trigonometry

Important terms-

1. Line of sight- The line of sight is the line drawn from the eye of an
observer to the point in the object viewed by the observer
2. Angle of Elevation- The angle of elevation of an object as seen
by an observer is the angle between the horizontal and the line
from the object to the observer's eye (the line of sight).

3. Angle of depression- If the object is below the level of the
observer, then the angle between the horizontal and the observer's
line of sight is called the angle of depression.

The height or length of an object or the distance between two distant
objects can be determined with the help of trigonometric ratios.

Example 1- A statue, 2 m tall, stands on the top of a pedestal. From
a point on the ground, the angle of elevation of the top of the statue
is 60° and from the same point the angle of elevation of the top of
the pedestal is 45°. Find the height of the pedestal.

a)

b)
c)
d) none of the above

Solution-

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