SOLUTION: Given: SinA = 77/85 and CosB = 80/89 Find: cos(A-B) I've been trying this problem over and over and have yet to get the right answer.

Question 935666: Given: SinA = 77/85 and CosB = 80/89
Find: cos(A-B)
I've been trying this problem over and over and have yet to get the right answer.
Answer by Alan3354(69443) (Show Source): You can put this solution on YOUR website!
Given: SinA = 77/85 and CosB = 80/89
Find: cos(A-B)
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Find cos(A) and sin(B)
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cos(A-B) = cos(A)cos(B) + sin(A)sin(B)

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