SOLUTION: cos(245)cos(5) + sin(245)sin(5)

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Question 756018: cos(245)cos(5) + sin(245)sin(5)
Answer by lwsshak3(11628)   (Show Source): You can put this solution on YOUR website!
cos(245)cos(5) + sin(245)sin(5)
Identity: cos(s-t)=cos s cos t+sin s sin t
cos(245)cos(5) + sin(245)sin(5)=sin(245-5)=sin 240º=-√3/2 (in Q3 where sin<0)

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