SOLUTION: cos(x-y) if cosx=5/12 and cosy=11/12

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Question 868290: cos(x-y) if cosx=5/12 and cosy=11/12
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
cos(x-y) if cosx=5/12 and cosy=11/12
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If cos(x) = 5/12; sin(x) = sqrt(12^2-5^2)/12 = sqrt(119)/12
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If cos(y) = 11/12; sin(y) = sqrt[12^2-11^2]/12 = sqrt(23)/12
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cos(x-y) = cos(x)cos(y) + sin(x)sin(y)
= (5/12)(11/12) + (sqrt(119)/12)(sqrt(23)/12)
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Cheers,
Stan H.