Question

No. 5nya please butuh banget cara jalannya!!!
#makasih

Answer 1

(sin x + 1)(sin x + 2) = cos² x
sin² x + 2sin x + sin x + 2 = 1 - sin^2 x
sin² x + 3sin x + 2 = 1 - sin² x
sin² x + sin² x + 3sin x + 2-1 = 0
2sin² x + 3sin x + 1 =0
(2sin x + 1)(sin x + 1) = 0
sin x = -0,5 atau sin x = -1
sin x = sin 210° atau sin x = sin 270°

uji
# x = β + k 360°
x = 210° + k 360°

k = -1
x = 210 - 360
x = -150 (Tidak memenuhi)

k = 0
x = 210 + 0.360
x = 210

k = 1
x = 210 + 360
x = 570 (tidak memenuhi)

#x = (β-180)° + k 360°
x = (210 - 180)° + k 360°
x = 30° + k 360°

k = -1
x = 30 - 360
x = -330 (Tidak memenuhi

k = 0
x = 30 + 0
x = 30

k = 1
x = 30 + 360
x = 390 ( Tidak memenuhi)

#x = β + k 360
x = 270 + k 360

k = 0
x = 270

#x = (β-180) + k 360
x = (270 - 180) + k 360
x = 90 + k 360

k = 0
x = 90

HP {30°, 90°, 210°,270°}