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Difficult general solution (1 Viewer)

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Hello all, I'm doing a JRAHS paper that my teacher gave me to do and I can't figure this one specific one out... maybe it's too late and its really simple and im just not seeing it. Only 2 marks and wolfram alpha gives quite a sophisticated answer...

Find the general solution for cos5x-cos2x=0
 

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Sorry what is the proof for that? Can't even remember that. #awkward
 

cineti970128

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General solution.
You can refer to your 3u textbook

Youknow about A S T C right??

First if cos(x) =cos a
For example cos x = .5 = cos60
Hence x= 60, 360-60, 360+ 60, 360 + (360-60),....
Hence similarly x = a, 360-a, 360+a, 720-a ...
X= 2pi*k +or - a
 

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