Question 859651
Solve the equation by first using a Sum-to-Product Formula. 
sin θ+ sin3θ=0 
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Sum to Product Formula::::
sin(a) + sin(b) = 2sin[(a+b)/2]cos[(a-b)/2]
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Your Problem:
sin(t) + sin(3t) = 2sin(4t/2)cos(2t/2) = 2sin(2t)cos(t)
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Cheers,
Stan H.
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