SOLUTION: Please help me answer this!! Use the identity cos(α+β)= cosαcosβ-sinαsinβ to find the value of cos 7pi/12 Please reply soon and Thaank you in

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Question 773663: Please help me answer this!!
Use the identity cos(α+β)= cosαcosβ-sinαsinβ to find the value of cos 7pi/12

Please reply soon and Thaank you in advance!!
Answer by ramkikk66(644)   (Show Source): You can put this solution on YOUR website!


pi/4 = 45 deg. 
pi/3 = 60 deg.  and 

So  =

Hope you got it :)

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