SOLUTION: sin(2x)+sin(x)=0 0<x<180

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Question 456549: sin(2x)+sin(x)=0 0
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
sin(2x)+sin(x)=0
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2sin(x)cos(x) + sin(x) = 0
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sin(x)[2cos(x)+1] = 0
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sin(x) = 0 or 2cos(x)+1 = 0
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x = 0 or pi or cos(x) = -1/2
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x = 0 or pi or (2/3)pi or (4/3)pi
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Cheers,
Stan H.