Pre Calculus

Use the sum-to-product formulas to find the exact value of the given expression.

sin 150° + sin 30°

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  1. Sorry, I have figured out this one but cannot figure out this one

    Use the sum-to-product formulas to write the given expression as a product. sin 4θ − sin 2θ

    Could you help me with this one instead please?

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  2. sum of sines:
    sinA + sinB = 2sin( (A+B)/2) cos( (A-B)/2)
    then:
    sin 150° + sin 30° = 2sin 90° cos 60°
    = 2(1)(1/2)
    = 1

    Difference of sines:

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

    then:
    sin 4θ − sin 2θ
    = 2cos(3Ø)sin Ø

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