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Express Each of the Following as the Product of Sines and Cosines: Sin 5x − Sin X - Mathematics

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Question

Express each of the following as the product of sines and cosines:
sin 5x − sin x

Sum
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Solution

\[\sin 5x - \sin x\]
\[ = 2\sin \left( \frac{5x - x}{2} \right) \cos \left( \frac{5x + x}{2} \right) \left\{ \because \sin A - \sin B = 2\sin\left( \frac{A - B}{2} \right)\cos\left( \frac{A + B}{2} \right) \right\}\]
\[ = 2 \sin 2x \cos 3x\]

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Transformation Formulae
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Chapter 8: Transformation formulae - Exercise 8.2 [Page 17]

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RD Sharma Mathematics [English] Class 11
Chapter 8 Transformation formulae
Exercise 8.2 | Q 1.2 | Page 17

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