SOLUTION: Find the exact value. sin(190)cos(55)-cos(190)sin(55)

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Question 959044: Find the exact value. sin(190)cos(55)-cos(190)sin(55)
Answer by Edwin McCravy(20064) About Me  (Show Source):
You can put this solution on YOUR website!
You must be able to recognize that as the right side of the identity

sin%28A-B%29%22%22=%22%22sin%28A%29cos%28B%29-cos%28A%29sin%28A%29

with substitutions A = 190° and B = 55°

sin%28%22190%B0%22-%2255%B0%22%29%22%22=%22%22sin%28%22190%B0%22%29cos%28%2255%B0%22%29-cos%28%22190%B0%22%29sin%28%2255%B0%22%29

sin%28%22190%B0%22-%2255%B0%22%29%22%22=%22%22sin%28%22135%B0%22%29%22%22=%22%22sqrt%282%29%2F2

Edwin