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Trigonometry with Rajesh Sir: Classes 10, 11 and 12

CBSE Mathematics · 2026–27

A triangle is only the beginning.

Move a side. Turn an angle. Watch a graph respond. Build trigonometry one idea at a time, with a question to try after every short topic.

Learn with Rajesh Sir

435θsin θ= 3/5Try it.

Pick your route. Keep your place in the syllabus.

Start where the ideas feel familiar. Each chapter ends with a checkpoint and a clear choice: practise at your current level or continue to the next.

Class 10

Begin with a triangle

Read the sides, build exact values and use a view to measure a height.

  1. Right-triangle ratios
  2. Standard angles and identities
  3. Heights and distances
Class 11

Let the angle travel

Move around the unit circle, read all six graphs and build new identities.

  1. Radians and the unit circle
  2. The six trigonometric graphs
  3. Compound and multiple angles
Class 12

Choose a branch. Find a change.

Reverse the functions carefully, then connect trigonometry with calculus.

  1. Inverse functions and principal values
  2. Limits and derivatives
  3. Trigonometric integrals

Learn it by changing it

The triangle lab keeps the right angle intact as you change P, B or H. Exact families give clean fractions; the unit circle and graph labs carry the same ideas further.

3 : 4 : 55 : 12 : 138 : 15 : 177 : 24 : 2520 : 21 : 29

Small steps, complete reasoning

Read. Build one idea with a diagram and a worked example. Try. Answer the short checks on the page. Explain. Use the written practice to show how you reached a result.

Use Print this topic inside a chapter for its explanation and diagram. Keep the questions on the screen, where hints and feedback help you work through them.