Trigonometry

If sinA + sinB = a and cosA + cosB = b, find the value of tanA-B/2

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  1. Recall your sum-to-product identities:

    sinA + sinB = 2 sin(A+B)/2 cos(A-B)/2
    cosA + cosB = 2 cos(A+B)/2 cos(A-B)/2

    That should get you started.

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  2. a/b is a value of tan[A-B/2]

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  3. Galat answer h chutiye

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