NCERT Class 10 Math Chapter 9 त्रिकोणमिति के कुछ अनुप्रयोग (Some Applications of Trigonometry) focuses on real-life uses of trigonometric concepts learned in the previous chapter. This chapter helps students connect mathematical formulas with practical problems like measuring heights and distances without directly measuring them. It is a scoring chapter in the exam because the problems are usually direct, based on simple trigonometric ratios. With good practice, students can easily solve all the questions in this section and gain full marks.
I am writing about this topic because many students understand formulas of trigonometry but struggle when it comes to applying them in real-world questions. This chapter simplifies that process by providing examples of how trigonometry is used in fields like architecture, navigation, and surveying. For example, calculating the height of a tower, the distance of a ship from the shore, or the angle of elevation of a kite are some situations explained in this lesson. I believe this chapter is important because it not only prepares students for board exams but also gives them a sense of how mathematics is practically useful. Having the NCERT PDF makes revision and practice easier, as all the exercises and solved examples are neatly compiled.
Main Topics in Chapter 9 त्रिकोणमिति के कुछ अनुप्रयोग
This chapter covers:
- Meaning of heights and distances in trigonometry
- Concept of angle of elevation and angle of depression
- Using trigonometric ratios in practical problems
- Word problems related to towers, buildings, ships, and shadows
Example for Understanding
If the angle of elevation of the top of a tree from a point on the ground is 45° and the distance from the tree is 20 m, then the height of the tree can be calculated using tan 45° = 1.
So, height = distance × tan 45° = 20 × 1 = 20 m.
This type of direct calculation makes the problems easy and clear.
Download PDF
Students can download NCERT Class 10 Math Chapter 9: त्रिकोणमिति के कुछ अनुप्रयोग PDF free of cost from here.
