SOLUTION: Given: sin A = 3/5 ,0 degrees < A < 90 degrees , and sin B = 8/17, 90 degrees < B < 180 degrees. Use the identity to find the exact value of cos(A-B)

Question 936326: Given: sin A = 3/5 ,0 degrees < A < 90 degrees , and sin B = 8/17, 90 degrees < B < 180 degrees. Use the identity to find the exact value of cos(A-B)
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
Given: sin A = 3/5 ,0 degrees < A < 90 degrees , and sin B = 8/17, 90 degrees < B < 180 degrees. Use the identity to find the exact value of cos(A-B)
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cos(A-B) = cos(A)cos(B)+sin(A)sin(B)
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= (4/5)(-15/17)+(3/5)(8/17)
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= (-60+24)/17
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= (36/17)
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Cheers,
Stan H.
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