Question

Find the solutions of the equation Cos2(theta)=3Cos(theta)-2 that are in the interval [0,2pi)

Answer 1

is it \[\cos 2 \theta or \cos^2\theta\]

Answer 2

cos^2 -3cos +2=0
c0s^2 -2cos -cos+2=0
cos(cos-2)-1(cos-2)=0
(cos-1)(cos-2)=0

Answer 3

cos=2 not possible as it give max value =1

Answer 4

cos theta =1

Answer 5

it give value =1
at 0 and 2pi