How do you solve #4\cos x = 1+ 2\cos x#?

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Answer 1 · 2017-03-05T10:32:39

#x=pi/3#

Rearrange to get all the #cos# over on one side.

#4cosx=1+2cosx#

#2cosx=1#

and now get it on its own by dividing by #2#,

#cosx = 1/2#

Now you can do an inverse function to find #x#:

#cosx = 1/2 -> cos^-1(1/2) = x#

#x = pi/3#