SOLUTION: To prove sin(theta+60)+sin(theta-60)=sin(theta)

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Question 1019431: To prove
sin(theta+60)+sin(theta-60)=sin(theta)

Answer by fractalier(6550) About Me  (Show Source):
You can put this solution on YOUR website!
To prove
sin%28theta%2B60%29%2Bsin%28theta-60%29=sin%28theta%29
expand sum and difference formulas and get

You can see that the 2nd and 4th terms cancel out...we get
sin%28theta%29cos%2860%29+%2B+sin%28theta%29cos%2860%29+=+sin%28theta%29
Since cos 60 = 1/2, we get
sin%28theta%29+=+sin%28theta%29