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Ch 03 -Trigonometric Functions — Revision Notes

ICSE · Class 11 · Mathematics

Ch 03 -Trigonometric Functions revision notes for ICSE Class 11 Mathematics: 4 topics in quick points. Part of the ICSE Class 11 Mathematics syllabus.

103 questions36 flashcards15 formulas & key relations5 concepts

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A diagram illustrating the definition of an angle as a measure of rotation, showing the initial side, terminal side, and vertex. It clearly distinguishes between positive (anti-clockwise) and negative
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Key Topics to Revise

1

1. Angles, Degree, and Radian

  • An angle is formed by two rays sharing a common end-point.
  • The common end-point is the vertex, and the rays are the sides of the angle.
  • Anticlockwise rotation is positive and clockwise rotation is negative.
2

2. Trigonometric Functions on the Unit Circle

  • A point P(a,b) on the unit circle is used to define trigonometric functions for any real angle x.
  • If arc AP = x, then sin x is the y-coordinate and cos x is the x-coordinate of P.
  • The domain of sine and cosine is all real numbers.
3

3. Trigonometric Identities and Allied Angles

  • A trigonometric identity is true for all values of the variable in its domain.
  • The Pythagorean identities are the backbone of many proofs.
  • Allied angles are angles whose sum or difference is 0 or a multiple of π/2.
4

4. Sum, Difference, and Compound-Angle Formulas

  • Sum and difference formulas are essential for evaluating non-standard angles.
  • They are used to derive many standard exact values such as sin 15°, cos 75°, and tan 105°.
  • These formulas also help prove identities involving two or more angles.

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Full Notes

Key Concepts

An angle is formed by twoA degree is 1/360 ofIf a circle has radius rFor a point P(asin x and cos x

Frequently Asked Questions

What are the important topics in Ch 03 -Trigonometric Functions for ICSE Class 11 Mathematics?
Key topics in Ch 03 -Trigonometric Functions include Angles, Degree, and Radian, Trigonometric Functions on the Unit Circle, Trigonometric Identities and Allied Angles, Sum, Difference, and Compound-Angle Formulas. Study these first, then practise questions on each for Class 11 exams.
How should I revise Ch 03 -Trigonometric Functions for Class 11 exams?
Learn the core ideas first, then work through the 103 practice questions on Ch 03 -Trigonometric Functions. Revise definitions regularly and use flashcards for quick recall before the exam.

Sources & Official References

Content is aligned to the official syllabus. Refer to the board website for the latest curriculum.

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