SOLUTION: cos200 degrees cos 20 degrees plus sin 200 degrees sin 20 degrees

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Question 1020479: cos200 degrees cos 20 degrees plus sin 200 degrees sin 20 degrees
Answer by fractalier(6550) About Me  (Show Source):
You can put this solution on YOUR website!
This is the cosine addition/subtraction formula in reverse...this equals
cos (200-20) = cos 180 = -1