SOLUTION: For all real numbers x, cos^2(x) - sin^2 (x)=? Thanks

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Question 24448: For all real numbers x, cos^2(x) - sin^2 (x)=?
Thanks
Answer by venugopalramana(3286) About Me  (Show Source):
You can put this solution on YOUR website!
THIS IS A STANDARD FORMULA AND IS EQUAL TO COS (2X)...THERE IS NOTHING MORE TO IT UNLESS YOU ARE TO PROVE THIS FORMULA.PLEASE GIVE ME YOUR COURSE OF STUDY AND YOUR BACK GROUND KNOWLEDGE SO THAT I CAN GIVE FURTHER ADVICE.
cos^2(x) - sin^2 (x)=?=COS(2X)
Thanks