SOLUTION: A and B are positive acute angles. Given: sinA = 77/85 and cosB = 80/89 Find cos( A

SOLUTION: A and B are positive acute angles. Given: sinA = 77/85 and cosB = 80/89 Find cos( A - B )

Question 935368: A and B are positive acute angles.
Given: sinA = 77/85 and cosB = 80/89
Find cos( A - B )
Answer by oscargut(2103) (Show Source): You can put this solution on YOUR website!

Use the formula: cos(a-b)= (cosa)(cosb)+(sena)(senb)

If you need more help or details you can contact me at:
mthman@gmail.com
Thanks
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