Ignore above
your equation is 2(cosx)^2-3cosx+1=0
use quadratic formula to get results
you will end up with
cosx=1 or cosx=1/2
so, x=0 or x=pi/3
your equation is 2(cosx)^2-3cosx+1=0
use quadratic formula to get results
you will end up with
cosx=1 or cosx=1/2
so, x=0 or x=pi/3