tentukan nilai x yang memenuhi kesamaan 2 cos (2x + 30 derajat) = akar 3 untuk 0 derajat < x < 360 derajat

2cos(2x + 30°) = √3
2cos(2x + 30°) = √3 (:2)
cos(2x + 30°) = (1/2)√3
acos(cos(2x + 30°)) = acos(1/2)√3
2x + 30° = 30°
2x = 30° - 30°
2x = 0°
2x = 0° (:2)
x₁ = 0°

2cos(2x + 30°) = √3
2cos(2x + 30°) = √3 (:2)
cos(2x + 30°) = (1/2)√3
acos(cos(2x + 30°)) = acos(1/2)√3
2x + 30° = 330°
2x = 330° - 30°
2x = 300°
2x = 300° (:2)
x₂ = 150°