Trigonify

Sum to Product

sin A + sin B

sin⁡A+sin⁡B=2sin⁡A+B2cos⁡A−B2\sin A + \sin B = 2 \sin\tfrac{A+B}{2} \cos\tfrac{A-B}{2}

Related Sum to Product identities

sin A - sin Bcos A + cos Bcos A - cos B

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