Question 927037
Find all solutions to the equation below on the interval [0, 2π). Enter them from smallest to largest; enter DNE in any empty blank.
{{{cos(2x)+cosx=2}}} 
{{{cos^2(x)-sin^2(x)+cosx=2}}}
{{{cos^2(x)-(1-cos^2(x))+cosx=2}}}
{{{cos^2(x)-1+cos^2(x)+cosx=2}}}
2cos^2(x)+cosx-3=0
(2cosx+3)(cosx-1)=0
2cosx+3=0
cosx=-3/2 (reject,-1 ≤ cosx ≤ 1
or
(cosx-1)=0
cosx=1
x=0