**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.