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प्रश्न
Express the following as a sum or difference
sin 35° cos 28°
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उत्तर
sin 35° cos 28°
We know
sin A cos B = `1/2`[sin (A + B) + sin (A – B)]
Take A = 35° and B = 28°
sin 35°cos 28° = `1/2`[sin(35° + 28°) + sin(35° – 28°)]
sin 35°cos 28° = `1/2`[sin 63° + sin 7°]
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