1. 2 cos (3x - 30°) = akar 3 , 0<_x<_360° cos (3x - 30°) = 1/2 (akar 3) cos (3x - 30°) = cos 30° 3x - 30° = 30° 3x = 30° + 30° 3x = 60° x = 60°/3 x = 20° atau 2 cos (3x - 30°) = akar 3 cos (3x - 30°) = 1/2 (akar 3) cos (3x - 30°) = cos 330° 3x - 30° = 330° 3x = 330° + 30° 3x = 360° x = 360°/3 x = 120° jadi hp nya adalah {20°,120°}
2. tan (1/2 x) = tan phi/6 , 0<_x<_2phi tan (1/2 x) = tan 180°/6 tan (1/2 x) = tan 30° 1/2 x = 30° x = 30° × 2 x = 60° x = 1/3 phi atau tan (1/2 x) = tan 210° 1/2 x = 210° x = 210° × 2 x = 420° x =/= 7/3 phi jadi hp nya adalah {1/3 phi}
Verified answer
1.2 cos (3x - 30°) = akar 3 , 0<_x<_360°
cos (3x - 30°) = 1/2 (akar 3)
cos (3x - 30°) = cos 30°
3x - 30° = 30°
3x = 30° + 30°
3x = 60°
x = 60°/3
x = 20°
atau
2 cos (3x - 30°) = akar 3
cos (3x - 30°) = 1/2 (akar 3)
cos (3x - 30°) = cos 330°
3x - 30° = 330°
3x = 330° + 30°
3x = 360°
x = 360°/3
x = 120°
jadi hp nya adalah {20°,120°}
2.
tan (1/2 x) = tan phi/6 , 0<_x<_2phi
tan (1/2 x) = tan 180°/6
tan (1/2 x) = tan 30°
1/2 x = 30°
x = 30° × 2
x = 60°
x = 1/3 phi
atau
tan (1/2 x) = tan 210°
1/2 x = 210°
x = 210° × 2
x = 420°
x =/= 7/3 phi
jadi hp nya adalah {1/3 phi}