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प्रश्न
Express the following as the sum or difference of sine or cosine:
cos 7θ sin 3θ
योग
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उत्तर
= `1/2` [sin(7θ + 3θ) – sin(7θ – 3θ)]
= `1/2` (sin 10θ – sin 4θ)
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Transformation Formulae
क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 4: Trigonometry - Exercise 4.3 [पृष्ठ ८८]
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