Some Applications of Trigonometry

9.1 Introduction

As we have studied about trigonometric ratios. Here will be studying about some ways in which trigonometry is used in the life around us.

9.2 Heights and Distances

In the figure line of sight is the line drawn from the eye of an observer to the point in the object viewed by the observer. The angle of elevation of the point viewed is the angle formed by the line of sight with the horizontal when the point being viewed is above the horizontal.

Thus, the angle of depression of a point on the object being viewed is the angle formed by the line of sight with the horizontal when the point is below the horizontal level, i.e., the case when we lower our head to look at the point being viewed.

1. 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. The angle of elevation of an object viewed, is the angle formed by the line of sight with the horizontal when it is above the horizontal level, i.e., the case when we raise our head to look at the object.

3. The angle of depression of an object viewed, is the angle formed by the line of sight with the horizontal when it is below the horizontal level, i.e., the case when we lower our head to look at the object.