Key Trigonometric Identities
- $\sin(A \pm B) = \sin A\cos B \pm \cos A\sin B$
- $\cos(A \pm B) = \cos A\cos B \mp \sin A\sin B$
- $\cos 2A = \cos^2A - \sin^2A = 2\cos^2A - 1 = 1 - 2\sin^2A = \frac{1 - \tan^2A}{1 + \tan^2A}$
High-yield revision notes, key concepts, formulas, and CBSE board examination questions for Class 11 Mathematics.
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