### Introduction

• Line of sight: A line joining the object and observer is known as line of sight.
• Horizontal line: The line which is parallel to the surface of the earth is called a horizontal line.
• Angle of elevation: If line of sight is above the horizontal line and the angle between the line of sight and horizontal line is known as horizontal line.
• Angle of depression: The line of sight is below the horizontal line and angle between the line of sight and the horizontal line is called the angle of depression.
• Theodolites: Theodolites is a process to measure angle of elevation or depression in the process of survey.

## Drawing figures to solve problems

• All objects such as towers, trees, buildings, ships, mountains, etc. Shall be considered as linear for mathematical convenience.
• The elevation angle of depression angle is taken into account in relation to the horizontal line.
• The height of the observer is neglected if it’s not given in the problem.

So now we have discussed the introduction of this application of trigonometry chapter so now let us discuss a few problems related to this chapter. #### Conclusion

This is the information about applications of trigonometry chapter. It is a very important chapter and a useful chapter. It helps in many of the competitive exams. Everyone should learn them and by learning this chapter we can get a lot of knowledge.