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Express Each of the Following as the Product of Sines and Cosines: Sin 12x + Sin 4x - Mathematics

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प्रश्न

Express each of the following as the product of sines and cosines:
sin 12x + sin 4x

बेरीज
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उत्तर

\[\sin 12x + sin 4x\]
\[ = 2\sin \left( \frac{12x + 4x}{2} \right) \cos\left( \frac{12x - 4x}{2} \right) \left\{ \because \sin A + \sin B = 2\sin \left( \frac{A + B}{2} \right) \cos \left( \frac{A - B}{2} \right) \right\}\]
\[ = 2 \sin 8x \cos 4x\]

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Transformation Formulae
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पाठ 8: Transformation formulae - Exercise 8.2 [पृष्ठ १७]

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आरडी शर्मा Mathematics [English] Class 11
पाठ 8 Transformation formulae
Exercise 8.2 | Q 1.1 | पृष्ठ १७

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