SOLUTION: How do you simplify this? (cos2x) / (cosx - sinx)

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Question 28886: How do you simplify this?
(cos2x) / (cosx - sinx)
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
You need to know that cos(2x)=(cosx)^2-(sinx)^2
Your problem becomes [(cosx)^2-(sinx)^2]/[cosx-sinx]
=cosx + sinx
Cheers,
Stan H.