SOLUTION: Find the exact value of the expression cos120(degrees)cos30(degrees)+sin120(degrees)sin30(degrees)

Question 852470: Find the exact value of the expression
cos120(degrees)cos30(degrees)+sin120(degrees)sin30(degrees)
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
Find the exact value of the expression
cos120(degrees)cos30(degrees)+sin120(degrees)sin30(degrees)
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Ans:: (-1/2)(sqrt(3)/2) + (sqrt(3)/2)(1/2) = 0
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OR
Your problem = cos(120-30) = cos(90) = 0
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cheers,
Stan H.
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