SOLUTION: Find the exact value of cos(-420º)

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Question 42389: Find the exact value of cos(-420º)
Answer by Nate(3500) About Me  (Show Source):
You can put this solution on YOUR website!
cos(-360º-60º)
cos(-2pi-%281%2F3%29pi)
cos(-(7/3)pi)
0.5
+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+10%2C+cos%28x%29%2C+0.5+%29+