SOLUTION: How do you prove the identity of sin(x+ pi)= sin(x)?

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Question 964516: How do you prove the identity of sin(x+ pi)= sin(x)?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
prove the identity of sin(x+ pi)= -sin(x)?
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Expand::
sin(x+pi) = sin(x)cos(pi)+cos(x)sin(pi)
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= sin(x)*(-1)+cos(x)*0
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= -sin(x)
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Cheers,
Stan H.
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