SOLUTION: Prove the following identity: cos(x-y)/cosxcosy=1+tanxtany

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Question 882094: Prove the following identity: cos(x-y)/cosxcosy=1+tanxtany
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
Prove the following identity: cos(x-y)/cosxcosy=1+tanxtany
cos%28x-y%29=%28cosx%2Acosy%2Bsinxsiny%29%2F%28cosxcosy%29
cos%28x-y%29=%281%2B%28sinxsiny%29%2F%28cosxcosy%29%29=1%2Btanxtany